Resin microparticle as raw material for toner, aqueous dispersed system thereof and toner

ABSTRACT

A resin microparticle for a toner raw material that has a small particle diameter and a narrow particle diameter distribution and has a low odor is provided. The resin microparticle for a toner raw material has the following requirements (i) to (iii) satisfied: Requirement (i): A particle diameter of 50% volume (D50) satisfies the relationship 0.05 μm≦D50≦1 μm; Requirement (ii): A particle diameter of 10% volume (D10) and a particle diameter of 90% volume (D90) satisfy the relationship D90/D10≦7; and Requirement (iii): The content of an organic solvent is not more than 70 ppm.

TECHNICAL FIELD

The present invention relates to a resin microparticle for a toner rawmaterial which has a uniform particle shape and form, an aqueousdispersed system having a microparticle in a disperse phase, and a tonercomprising the microparticle.

BACKGROUND ART

As production method of a toner for electrostatic development, akneading and grinding method has been widely used. A toner forelectrostatic development obtained by that method tends to has a wideparticle size distribution and has a lot of coarse powders and finepowders. Therefore, it is pointed out that the deterioration of imagequality and a carrier pollution by the toner easily occur. Furthermore,for producing a toner having a small particle diameter and a narrowparticle size distribution by the kneading and grinding method, muchenergy may be required in some cases.

As a method for producing an aqueous dispersed system of a resinmicroparticle, a method using a twin screw extruder has been disclosed(refer to Patent Document 1). That is a method comprising dissolving apolyester resin in an organic solvent to have a viscosity capable ofemulsification and adding water thereto for the phase inversionemulsification. Since that method employs an organic solvent, a processfor removing such a solvent is troublesome and there is also a problemof economical efficiency. Further, it is difficult to completely removean organic solvent from the aqueous dispersed system. Therefore, thereare problems of environmental contamination, safety, odor and the likecaused by the organic solvent.

Meanwhile, there has also been proposed a method comprising melting araw material for a toner comprising a polyester resin, adding water tothe melted product for the phase inversion emulsification to form aresin microparticle, and agglomerating and fusing the formed resinmicroparticle to obtain a toner (refer to Patent Document 2). In thePatent Document 2, a microparticle having a particle diameter of notless than 2.4 μm before fusion has only been disclosed. In that method,since a particle diameter of the microparticle before fusion is big,there has been a problem that it is not possible to obtain a resinmicroparticle having physical properties that the present inventors havetargeted.

Patent Document 1: JP1998-139884A

Patent Document 2: JP2002-351140A

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

An object of the present invention is to provide a resin microparticlefor a toner raw material that has a small particle diameter and a narrowparticle diameter distribution, having low odor. Furthermore, theinvention is to provide a toner comprising the resin microparticle andan aqueous dispersed system of the resin microparticle.

MEANS FOR SOLVING THE PROBLEM

In order to achieve the above objects, the present inventors haveconducted an extensive study. As a result, they have found that a resinis melted and mixed in the presence of water to form a resinmicroparticle for a toner and the thus-formed resin microparticle hasexcellent performance. Thus, the present invention has been completed.

That is, the present invention relates to:

(1) a resin microparticle (A) for a toner raw material satisfying all ofthe following requirements (i) to (iii):

Requirement (i): A particle diameter of 50% volume (D50) satisfies therelationship 0.05 μm≦D50≦1 μm;

Requirement (ii): A particle diameter of 10% volume (D10) and a particlediameter of 90% volume (D90) satisfy the relationship D90/D10≦7; and

Requirement (iii): The content of an organic solvent is not more than 70ppm;

(2) an aqueous dispersed system comprising the above resin microparticle(A) for a toner raw material dispersed in water; and

(3) a toner comprising the above resin microparticle (A) for a toner rawmaterial.

EFFECT OF THE INVENTION

The resin microparticle according to the present invention has aparticle diameter of 50% volume (D50) of 0.05 μm≦D50≦1 μm so that acomponent such as a dye or a wax is satisfactorily dispersed in thepreparation of a toner. Further, the resin microparticle has therelationship of a particle diameter of 10% volume D(10) and a particlediameter of 90% (D90) of D90/D10≦7 so that a toner obtained from theresin microparticle does not contaminate a carrier, thus resulting inobtaining excellent image quality. Further, the resin microparticle hasthe content of an organic solvent of not more than 70 ppm so that atoner obtained from the resin microparticle produces low order. Thus,the toner is preferable from the viewpoint of working environment aswell. Therefore, the resin microparticle of the present invention can besuitably used for a toner raw material.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in more detail below.

In the present invention, a particle diameter of 50% volume (D50) of theresin microparticle (A) for a toner raw material is 0.05 μm≦D50≦1 μm,and preferably 0.1 μm≦D50≦0.7 μm. Furthermore, the relationship betweena particle diameter of 10% volume (D10) and a particle diameter of 90%volume (D90) of the resin microparticle (A) for a toner raw material isD90/D10≦7, and preferably D90/D10≦4.5. When the particle diameter of theresin microparticle (A) is within the above range, a toner having asmall particle diameter distribution can be obtained in the preparationof a toner using such a microparticle. Furthermore, dispersability of acomponent such as a colorant, a releasing agent, a charge controllingagent or the like in the toner becomes good so that compositions betweentoners become homogeneous. Thus, performance or reliability as a toneris stable.

In the present invention, the content of an organic solvent in the resinmicroparticle (A) for a toner raw material is not more than 70 ppm andpreferably not more than 30 ppm. When the content of the organic solventin the resin microparticle (A) is within the above range, a tonerwithout having problems of environmental contamination or odor can beobtained. In case the organic solvent remains in the toner, a lowmolecular weight component in the toner particle or a non-polarcomponent such as a wax having a low melting point is considered to beconveyed to a surface of the toner particle with volatilizing theorganic solvent gradually. For this reason, the deterioration in storagestability or development properties of the toner easily takes place.However, the toner according to the present invention does notpractically contain an organic solvent so that a toner with excellentstorage stability (anti-blocking properties) and development stabilitycan be obtained.

In the present invention, an organic solvent is not restricted as far asit is volatile. Concrete examples thereof include aromatic hydrocarbonsolvents such as toluene, xylene, ethylbenzene, tetralin and the like;aliphatic or alicyclic hydrocarbon type solvent such as n-heptane,n-hexane, cyclohexane and the like; halogen series solvents such asmethylene dichloride, carbon tetrachloride and the like; ester or esterether solvents such as ethyl acetate, butyl acetate, methylcellosolveacetate and the like; ether solvents such as diethyl ether,tetrahydrofuran and the like; ketone solvents such as acetone,methylethyl ketone and the like; and alcohol solvents such as methanol,ethanol, isopropanol, n-butanol, benzyl alcohol and the like.

In the present invention, the aqueous dispersed system comprising theresin microparticle (A) for a toner raw material dispersed in water canbe preferably produced by melt-mixing a resin in the presence of water.A method for melt-mixing is not particularly restricted, but an extruderis preferably used from the viewpoint that the resin can be heated up tonot less than the plasticizing temperature of the resin and the resincan be mechanically mixed sufficiently. A twin screw extruder capable ofcarrying out melt-mixing and phase inversion is particularly preferable.Furthermore, a twin screw extruder with a water inlet placed at a ventsection is preferable from the viewpoint that melt-mixing and phaseinversion can be continuously carried out.

The preferred range of a temperature for carrying out melt-kneading isdifferent depending on the melting temperature of a resin. However, itis preferably from 80° C. to 180° C. from the viewpoint of kneadingefficiency. It is more preferably from 80° C. to 170° C. and furtherpreferably from 80° C. to 155° C. When melt-kneading is carried out inthe above temperature range, the resin can be fully mixed anddecomposition of the resin can be prevented.

In case the dispersed system of the present invention is produced byusing a twin screw extruder, it is preferable that a single screwextruder is placed at an outlet of the above extruder to pass thedispersed system through the single screw extruder for cooling it downto not more than 100° C.

In the present invention, when water is fed, the amount of water ispreferably from 5 mass % to 50 mass % and more preferably from 10 mass %to 30 mass % in the total amount of a polyester type resin (B) andwater. The amount of water within the above range is preferable from theviewpoint that a resin microparticle satisfying the relationships of D10and D90 of D90/D10≦7 and D50 of 0.05 μm≦D50≦1 μm can be easily obtained.

In the present invention, ion exchange water is suitably used for water,whereas a basic aqueous solution may be used as well. Preferableexamples of the basic aqueous solutions may include the aqueous solutionof the substances worked as bases such as alkali metals, alkali earthmetals, ammonia, oxides of alkali metals and alkali earth metals,hydroxides and the like. More preferred examples thereof may includeaqueous solutions of sodium oxide, sodium peroxide, potassium oxide,potassium peroxide, strontium oxide, barium oxide, sodium hydroxide,potassium hydroxide, calcium hydroxide, strontium hydroxide, bariumhydroxide and the like. A concentration of the basic aqueous solution ispreferably not more than 1N and more preferably not more than 0.5N.

In the production method of the present invention, by changing theconditions such as the thermal fusion time and temperature afteraggregation a toner having an uneven surface, a toner having a slightlydissimilar shape compared to the complete spherical shape, and the likemay be produced. Thus, the toner shape can be controlled flexibly.Therefore, a toner with excellent cleaning properties can be produced.

In the present invention, the term “polymerization” may include themeaning of copolymerization, and the term “polymer” may have the meaningof a copolymer.

A resin contained in the resin microparticle (A) for a toner rawmaterial used in the present invention is not particularly restricted asfar as it is easily dissolved in water or a basic aqueous solution. Anyof resins which have been conventionally used as a resin for toner canbe suitably used. Examples thereof include a polyether polyol basedresin, a polyester based resin, a styrene based resin, an acryl basedresin and the like. Among these resins, a polyester based resin (B) anda polyether polyol based resin (D) are particularly preferable.

The polyester based resin (B) is excellent in offset resistance,durability, low-temperature fixing properties and the like in the caseof using it as a toner. In the present invention, the polyester basedresin (B) is a resin (polyester resin (a)) obtained by carrying outpolycondensation of at least one kind of a polyhydric alcohol and atleast one kind of a polycarboxylic acid as main components. Furthermore,the polyester based resin (B) in the present invention includes aurethane modified polyester resin (a1) obtained by reacting thepolyester resin (a) and a polyisocyanate (b) as well. The primarystructure of the polyester based resin (B) is not particularlyrestricted. Any of a linear resin, a branched resin or a crosslinkedresin can be used.

Examples of the polyhydric alcohols which are used as a raw material ofthe polyester resin (a) include dihydric alcohols such as aromaticdiols, aliphatic diols, alicyclic diols, and tri- or higher polyhydricalcohol. Examples of the aromatic diols include o-xylylene glycol,p-xylylene glycol, m-xylylene glycol, ethylene oxide adducts ofbisphenol A, propylene oxide adducts of bisphenol A and the like.Examples of ethylene oxide adducts of bisphenol A includepolyoxyethylene-(2,0)-2,2-bis(4-hydroxyphenyl)propane and the like.Examples of propylene oxide adducts of bisphenol A include,polyoxypropylene-(2,0)-2,2-bis(4-hydroxyphenyl)propane,polyoxypropylene-(1,2)-2,2-bis(4-hydroxyphenyl)propane,polyoxypropylene-(1,1)-2,2-bis(4-hydroxyphenyl)propane,polyoxypropylene-(2,2)-polyoxyethylene(2,0)-2,2-bis(4-hydroxyphenyl)propane,polyoxypropylene-(6)-2,2-bis(4-hydroxyphenyl)propane,polyoxypropylene-(3,3)-2,2-bis(4-hydroxyphenyl)propane and the like.Examples of the aliphatic diols include ethylene glycol, diethyleneglycol, 1,2-propanediol, 1,3-propanediol, triethylene glycol,1,3-butanediol, 2,3-butanediol, 1,4-butanediol, 1,5-pentanediol,neopentyl glycol, dipropylene glycol, 1,6-hexanediol,2-ethyl-1,3-hexanediol and the like. Examples of the alicyclic diolsinclude dihydroxymethyl cyclohexane, hydrogenated bisphenol A and thelike. Among these compounds, preferable are ethylene oxide adducts ofbisphenol A, propylene oxide adducts of bisphenol A, diethylene glycol,triethylene glycol, ethylene glycol and neopentyl glycol. Morepreferable are propylene oxide adducts of bisphenol A, triethyleneglycol, ethylene glycol and neopentyl glycol.

Examples of the polycarboxylic acid which is used as a raw material ofthe polyester resin (a)include aliphatic saturated dicarboxylic acids,aliphatic unsaturated dicarboxylic acids and aromatic dicarboxylicacids. Furthermore, they include anhydrides of the above variousdicarboxylic acids or dicarboxylic acids of lower alkyl esters having 1to 6 carbon atoms. Examples of the aliphatic saturated dicarboxylicacids include malonic acid, succinic acid, glutaric acid, adipic acid,azelaic acid, sebacic acid and the like. Examples of the aliphaticunsaturated dicarboxylic acids, include maleic acid, fumaric acid,citraconic acid, itaconic acid and the like. Examples of aromaticdicarboxylic acidsinclude phthalic acid, terephthalic acid, isophthalicacid, 1,5-naphthalic acid and the like. Examples of anhydrides of theabove various dicarboxylic acidsinclude succinic anhydride, maleicanhydride, phthalic anhydride and the like. Examples of the lower alkylesters having 1 to 6 carbon atoms of the above various dicarboxylicacidsinclude dimethyl succinate, diethyl maleate, dihexyl phthalate andthe like. Among these, preferably used are adipic acid, terephthalicacid and isophthalic acid, while more preferably used are terephthalicacid and isophthalic acid.

Furthermore, as a raw material of the polyester resin (a), tri- orhigher polyhydric alcohol, tri- or higher polycarboxylic acid andanhydrides thereof can also be used as needed. Examples of the tri- orhigher polyhydric alcohols include glycerin, 2-methylpropanetriol,trimethylolpropane, trimethylolethane, sorbitol, sorbitan and the like.Examples of the tri- or higher polycarboxylic acidsinclude trimelliticacid, pyromellitic acid and the like.

It is also possible to use a monocarboxylic acid and a monohydricalcohol. Examples of the monocarboxylic acidsinclude aliphaticmonocarboxylic acids having a straight chained structure, a branchedstructure an unsaturated structure and aromatic monocarboxylic acids.Examples of the aliphatic monocarboxylic acid include octanoic acid,decanoic acid, dodecanoic acid, myristic acid, palmitic acid, stearicacid and the like. Examples of the aromatic monocarboxylic acidsincludebenzoic acid, naphthalenecarboxylic acid and the like. Aliphaticmonohydric alcohols such as octanol, decanol, dodecanol, myristylalcohol, palmityl alcohol, stearyl alcohol and the like can also beused. Preferable are glycerin, trimethylolpropane, stearic acid,trimellitic acid and benzoic acid. More preferable aretrimethylolpropane, stearic acid and benzoic acid.

By using these compounds, the molecular weight and glass transitiontemperature (Tg) of the polyester resin (a) can be controlled, and alsoa branched structure can be introduced. In particular, to obtain aurethane modified polyester resin (a1) which is crosslinked orpolymerized with a polyisocyanate to be described later (hereinafter,described as urethane-extending in some cases), as a raw material of thepolyester resin (a), one or more kinds of tri- or higher polyhydricalcohols are preferably used from the viewpoint of effectivepolymerization.

The amount of the tri- or higher polyhydric alcohol is preferably in therange of 0.25 mole % to 25 mole % and more preferably in the range of0.5 mole % to 20 mole % in the total alcohol components, raw materialsof the polyester resin (a) (total amount of diol and tri- or higherpolyhydric alcohol). The amount of the tri- or higher polyhydric alcoholwithin the above range is preferable in that polycondensation reactionproperly takes place during urethane-extending of the polyester resin(a), thus enhancing offset resistance or durability of the toner.

The temperature of polycondensation reaction is generally from 150° C.to 300° C., preferably from 180° C. to 270° C. and more preferably from200° C. to 250° C. The reaction temperature within the above range ispreferable in that the polyester resin (a) with good productivity can beobtained within a short period of time without causing decomposition ofthe resin.

In the polycondensation reaction, the addition of a catalyst ispreferable because the reaction proceeds rapidly. As the catalyst, knowncatalysts for use in the polycondensation reaction can be used. Examplesthereof include catalysts containing elements such as tin, antimony,titanium, germanium, aluminum and the like. Examples of the catalystscontaining tin include dibutyltin oxide and the like. Examples of thecatalysts containing antimony include antimony trioxide and the like. Asthe catalyst containing titanium, titanium alkoxide, titanium acylate,titanium chelate and the like can be more preferably used, andtetra-n-butyl titanate, tetra(2-ethylhexyl)titanate, tetramethyltitanate and tetraisopropyl titanate are particularly preferably used.Examples of the catalysts containing germanium include germanium dioxideand the like.

The amount of the catalyst added is preferably from 0.01 mass part to1.00 mass part per 100 mass parts of a monomer. The above catalyst maybe used singly or in combination. Further, the catalyst may be added atthe beginning or in the middle of polymerization.

To produce the urethane modified polyester resin (a1), the hydroxylvalue of the polyester resin (a) to be reacted wit the polyisocyanate(b) is preferably from 5 KOHmg/g to 100 KOHmg/g and more preferably from5 KOHmg/g to 80 KOHmg/g. The hydroxyl value within the above range ispreferable from the viewpoint of proper reactivity in urethane extendingof the polyester resin (a). For that reason, gel portion in the resinbecomes proper so that both good offset resistance and fixing propertiescan be exhibited ; therefore the above range is preferable. The hydroxylvalue refers to mg of potassium hydroxide necessary to neutralize theacid anhydride necessary to esterify the hydroxyl group present in 1 gof the resin.

To produce the urethane modified polyester resin (a1), the acid value ofthe polyester resin (a) to be reacted wit the polyisocyanate (b) ispreferably not more than 100 KOHmg/g and more preferably from 1 KOHmg/gto 80 KOHmg/g. The acid value within the above range is preferable fromthe viewpoint that the toner exhibits excellent electrificationstability. The acid value in the present invention refers to mg ofpotassium hydroxide necessary to neutralize 1 g of the resin.

The number-average molecular weight (Mn) of the THF soluble component ofthe polyester resin (a) is preferably from 1,000 to 50,000, morepreferably from 1,000 to 20,000, and further preferably from 1,500 to8,000. The number-average molecular weight within the above range ispreferable from the viewpoint that excellent offset resistance,durability and fixing properties of the toner can be obtained.

It is preferable that the THF soluble component of the polyester resin(a) has at least one peak in the range of 3,000 to 10,000 molecularweight in the molecular weight distribution measured by the gelpermeation chromatography (GPC). This is preferable because fixingproperties and gloss of the toner becomes excellent.

A glass transition temperature (Tg) of the polyester resin (a) ispreferably from 30° C. to 80° C. and more preferably from 40° C. to 70°C. Tg within the above range is preferable from the viewpoint that atoner exhibiting good storage stability and fixing properties can beobtained.

In the present invention, the polyester based resin (B) may be usedtogether with two kinds or more polyester resins (a). In that case, evenwhen characteristics of respective acid values or hydroxyl values areout of the above range, those of the whole polyester based resin (B) arepreferably within the above range.

The polyester based resin (B) of the present invention contains the THFinsoluble component in an amount of from 0.3 mass % to 20 mass % andmore preferably in an amount of from 0.5 mass % to 10 mass %. The THFinsoluble component within the above range is preferable becausesufficient offset resistance and fixing properties can be obtained.

It is preferable that the THF insoluble component of the polyester basedresin (B) in the present invention contains a polyisocyanate-derivedstructure unit. The structure unit is obtained by, for example, reactinga hydroxyl group of the polyester resin (a) with the polyisocyanate (b).Therefore, the polyester resin (a) and polyisocyanate (b) are preferablyused in an amount of from 0.1 mole part to 2.5 mole parts and morepreferably from 0.2 mole part to 2.0 mole parts of an isocyanate groupof the polyisocyanate (b) for 1 mole part of the hydroxyl group of thepolyester resin (a). When the amount of the polyisocyanate (b) is small,the toner does not exhibit sufficient offset resistance in some cases.When the amount of the polyisocyanate (b) is high, there is a problem ofstability in some cases because unreacted polyisocyanate remains in theresin after the reaction.

Polyisocyanate (b) in the present invention is a compound having two ormore isocyanate groups in a molecule. As the diisocyanate compoundcontaining two isocyanate groups in a molecule, there can beexemplified, for example, alicyclic diisocyanate, alicyclicdiisocyanate, aromatic diisocyanate, aralkyl diisocyanate and the like.Examples of the aliphatic diisocyanates include hexamethylenediisocyanate (HDI), tetramethylene diisocyanate and the like. Examplesof the alicyclic diisocyanates include isophorone diisocyanate (IPDI),norbornene diisocyanate (NBDI), hydrogenated diphenylmethanediisocyanate and the like. As the aromatic diisocyanate, there can beexemplified, for example, tolylene diisocyanate (TDI), diphenylmethanediisocyanate (MDI) and the like. Examples of the aralkyl diisocyanateinclude xylylene diisocyanate (XDI) and the like.

Furthermore, polyisocyanates containing three or more isocyanate groupsin a molecule such as polyphenylene polymethylene polyisocyanate(polymeric MDI) and the like can also be used. Also, modifiedpolyisocyanates obtained by various modifications such as biuretmodification, allophanate modification, isocyanurate modification,urethane modification and the like can be used. Among these, aromaticpolyisocyanate is one of polyisocyanates which can be the most suitablyused since it is highly reactive and cheap.

Preferred examples of methods for reacting the polyester resin (a) withthe polyisocyanate (b) include the method comprising feeding thepolyester resin (a) into a twin screw extruder for kneading, and thenfeeding the polyisocyanate (b) into the resin mixture during kneadingand conveying for further melt-kneading. Examples of reactors used inthe other method than those above include a single screw extruder, astatic mixer and a usual reactor with a stirrer.

The reaction temperature is preferably in the range of 100° C. to 200°C. and more preferably in the range of 140° C. to 190° C. The reactiontemperature within the above range is preferable since the resin is notpyrolytically decomposed and urethane extending reaction occurssufficiently, thus resulting in obtaining offset resistance of a toner.

Furthermore, urethane extending of the polyester resin (a) may becarried out in the presence of a component selected from a colorant, acharge controlling agent, a releasing agent or the like. In addition,other resins such as a styrene-acrylic binder resin, a polyol basedbinder resin or the like can be contained as far as the characteristicsare not damaged.

The amount and structure of the THF insoluble component are determinedby using the resin microparticle obtained by drying a dispersed systemwith a resin microparticle for a toner dispersed therein at 150° C. for2 hours and then cooled and solidified.

The structure of the toner binder resin can be analyzed by thecombination of known analytical methods such as infrared spectroscopy(IR), ultraviolet spectroscopy, nuclear magnetic resonance spectroscopy(NMR), liquid chromatography (LC), mass spectrometry (MS) resinhydrolysis, distillation and the like. Since the THF insoluble componentis hardly dissolved in a solvent, a analytical method is a littlerestricted. However, the structure can be specified by carrying outthorough hydrolysis of the THF insoluble component and then separatingby distillation or LC, and analyzing by the combination of methods suchas gas chromatography (GC) as well as IR, NMR, LC and MS.

The polyester based resin (B) in the present invention is preferably apolyester based resin (B1) having a sulfonic acid group. In the presentinvention, the sulfonic acid includes its metal salt or ammonium salt.

Examples of the monomers having a sulfonic acid group and/or a sulfonicacid metal salt group which is used as a raw material of the polyesterbased resin (B) include sulfoisophthalic acid, 5-sulfoisophthalic acid,4-sulfophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid,5-(4-sulfophenoxy)isophthalic acid, 5-(sulfopropoxy)isophthalic acid,sulfopropyl malonic acid, sulfosuccinic acid, 2-sulfobenzoic acid,3-sulfobenzoic acid, 5-sulfosalicylic acid and methyl esters of thesecarboxylic acids. Furthermore, metal salts such as lithium, natrium,kalium, magnesium, calcium, copper, iron or the like of these sulfonicacids, or ammonium salts are included.

A polyfunctional monomer containing a sulfonic acid group comprising atleast one or more hydroxyl groups can also be used. The polyfunctionalmonomer is obtained by reacting glycidyl alcohols such as2,3-epoxy-1-propanol, 3,4-epoxy-1-butanol or the like; difunctionalepoxy such as ethylene glycol diglycidyl ether, diethylene glycoldiglycidyl ether, triethylene glycol diglycidyl ether or the like; tri-or higher functional epoxy such as trimethylol propane triglycidyl etheror the like with acidic sulfite at 20° C. to 200° C. in the presence ofa catalyst such as amine or imidazole as needed.

Among these, 5-sulfoisophthalic acid, sodium 5-sulfoisophthalic acid andsodium dimethyl 5-sulfoisophthalic acid are suitably used.

The amount of the monomer having a sulfonic acid group is preferablyfrom 0.5 mole part to 8 mole parts and more preferably from 0.5 molepart to 4 mole parts per the total 100 mole parts of the polycarboxylicacid-derived structure unit and polyhydric alcohol-derived structureunit constituting the polyester based resin (B). The amount used is thesame when the polyester based resin (B) is a polyester based resin (B11)having a vinyl copolymer-derived structure (C). The amount of themonomer having a sulfonic acid group and/or a sulfonic acid metal saltgroup within the above range is preferable because the particle diameterof 50% volume of the resin microparticle in a suspension becomes notmore than 1 μm and toner storage stability becomes good when it ismelt-mixed in the presence of water.

In the present invention, the polyester based resin (B) is alsopreferably a polyester based resin (B11) having a vinylcopolymer-derived structure (C).

The vinyl copolymer-derived structure (C) in the present invention is aportion derived from the corresponding vinyl copolymer (c). The contentof the vinyl based copolymer-derived structure (C) is from 0.5 mass % to10 mass %, and preferably from 0.5 mass % to 6 mass % in the polyesterbased resin (B11). The content of the vinyl copolymer-derived structure(C) within the above range is preferable in that a resin microparticlefor a toner having a small particle diameter and a narrow particlediameter distribution can be easily obtained and also the releasingagent component can be dispersed well when it is used for a toner.Examples of methods for producing the polyester based resin (B11)include the method of urethane-extending of the melted mixture of thepolyester resin (a) and vinyl based copolymer (c) and the methodcomprising urethane-extending only the polyester resin (a) and thenadding the vinyl copolymer (c) thereto for melt-kneading again. Themethod of grounding each of the urethane-extended polyester resin (a1)and the vinyl copolymer (c) powders and mixing them is also includedbecause the polyester resin (a1) and the vinyl polymer (c) are partlyreacted while the mixed resin is kneaded in the presence of water. Amongthese methods, in consideration of dispersability of the vinyl copolymer(c) into the polyester resin (a), a method of urethane-extending of themelted mixture of the polyester resin (a) and vinyl copolymer (c) ispreferable.

The vinyl copolymer (c) of the present invention is obtained bypolymerizing at least one kind of a vinyl monomer.

As the polymerization method, known methods such as solutionpolymerization, bulk polymerization, suspension polymerization, emulsionpolymerization or the like can be employed. However, a method comprisingcarrying out solution polymerization in an organic solvent and removingthe solvent is preferably used from the viewpoint of its convenience. Asthe solvent for the solution polymerization, aromatic hydrocarbons suchas benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, cumeneand the like are used. These can be used singly or in combinationthereof, whereas the molecular weight can also be adjusted by the use ofother solvent(s).

Any polymerization initiators can be usually used as far as they can beused as radical polymerization initiators. Examples thereof include azoinitiators such as 2,2′-azobisisobutyronitrile,2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile),2,2′-azobis(2,4-dimethylvaleronitrile),2,2′-azobis(2-methylbutyronitrile), dimethyl-2,2′-azobisisobutyrate, 1,1′-azobis(1-cyclohexanecarbonitrile), 2-(carbamoylazo)-isobutyronitrile,2,2′-azobis(2,4,4-trimethylpentane),2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile,2,2′-azobis(2-methylpropane) and the like; ketone peroxides such asmethylethylketone peroxide, acetylacetone peroxide, cyclohexanoneperoxide and the like; peroxy ketals such as1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)butane and thelike; hydroperoxides such as t-butyl hydroperoxide, cumenehydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide and the like;dialkyl peroxides such as di-t-butyl peroxide, t-butylcumyl peroxide,dicumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane,α,α′-bis(t-butylperoxyisopropyl)benzene and the like; diacyl peroxidessuch as isobutyryl peroxide, octanoyl peroxide, decanoyl peroxide,lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide,m-toluoyl peroxide and the like; peroxydicarbonates such as diisopropylperoxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-n-propylperoxydicarbonate, di-2-ethoxyethyl peroxycarbonate, dimethoxyisopropylperoxydicarbonate, di(3-methyl-3-methoxybutyl)peroxycarbonate and thelike; sulfonyl peroxides such as acetylcyclohexyl sulfonyl peroxide andthe like; and peroxyesters such as t-butyl peroxyacetate, t-butylperoxyisobutyrate, t-butyl peroxyneodecanoate, cumyl peroxyneodecanoate,t-butyl peroxy-2-ethylhexanoate, t-butyl peroxy laurate, t-butyl peroxybenzoate, t-butyl peroxy isopropyl carbonate, di-t-butyldiperoxyisophthalate and the like. These compounds are used singly or incombination of two or more kinds. The type and amount of polymerizationinitiator can be suitably selected depending on the reactiontemperature, concentration of the monomer and the like. The amountthereof is preferably from 0.01 weight part to 10 weight parts per 100weight parts of the raw material monomer.

Examples of the vinyl monomers as a raw material of the vinyl copolymer(c) of the present invention include acrylic esters such as methylacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octylacrylate, cyclohexyl acrylate, lauryl acrylate, stearyl acrylate, benzylacrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, ethoxylacrylate, butoxyl acrylate, dimethylaminomethyl acrylate ester,dimethylaminoethyl acrylate ester and the like; methacrylic esters suchas methyl methacrylate, ethyl methacrylate, propyl methacrylate, butylmethacrylate, octyl methacrylate, lauryl methacrylate, stearylmethacrylate, cyclohexyl methacrylate, benzyl methacrylate, furfurylmethacrylate, tetrahydrofurfuryl methacrylate, hydroxyethylmethacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate,dimethylaminomethyl methacrylate ester, dimethylaminoethyl methacrylateester and the like; aromatic vinyl monomers such as styrene, vinyltoluene, α-methylstyrene, chlorostyrene and the like; dialkyl esters ofan unsaturated dibasic acid such as dibutyl maleate, dioctyl maleate,dibutyl fumarate, dioctyl fumarate and the like; vinyl esters such asvinyl acetate, vinyl propionate and the like; nitrogen-containing vinylmonomers such as acrylonitrile, methacrylonitrile, acrylamide,methacrylamide, N-substituted acrylamide, N-substituted methacrylamideand the like; divinyl compounds such as divinyl benzene, (poly)ethyleneglycol diacrylate, (poly)ethylene glycol dimethacrylate and the like;conjugated diolefin unsaturated monomers such as butadiene, chloroprene,neoprene, isobutylene and the like; glycidyl group-containing vinylmonomers such as glycidyl acrylate, β-methyl glycidyl acrylate, glycidylmethacrylate, β-methyl glycidyl methacrylate and the like. These vinylmonomers are used singly or in combination of two or more kinds. Amongthese, particularly preferable examples of the vinyl monomer includestyrenes, acrylic acids, methacrylic acids acrylic esters, methacrylicesters and glycidyl group-containing monomers.

The number-average molecular weight of the vinyl copolymer (c) of thepresent invention is preferably from 1,000 to 30,000 and more preferablyfrom 3,000 to 25,000. The number-average molecular weight of the vinylcopolymer (c) within the above range is preferable from the viewpointsthat a toner having good dispersability into the polyester based resinand a toner with good storage stability can be obtained.

The vinyl copolymer (c) preferably contains the glycidylgroup-containing monomer in the range of 0.3 mole part to 13 mole partsper the total 100 mole parts of all vinyl monomers as a raw material.The range of 0.6 mole part to 13 mole parts is more preferable from theviewpoint of the dispersability of the vinyl copolymer into thepolyester based resin.

The polyester based resin (B1) in the present invention is preferably apolyester based resin (B12) which does not include the bisphenolA-derived structure unit and contains not more than 5 ppm tin. In thepresent invention, the bisphenol A-derived structure unit is representedby the following formula (1).

The bisphenol A-derived structure is not included in the polyester basedresin (B12) from the viewpoint of reduced environmental burdens. Namely,polyhydric alcohols in the preparation of the polyester based resin(B12) do not include bisphenol A, bisphenol A-2 propylene oxide adducts,bisphenol A-3 propylene oxide adducts, bisphenol A polypropylene oxideadduct, bisphenol A-2 ethylene oxide adducts, bisphenol A-3 ethyleneoxide adducts and bisphenol A polyethylene oxide adduct. In the presentinvention, the meaning of not including the bisphenol A-derivedstructure is that the bisphenol A-derived structure is preferablycontained in an amount of not more than 0.5 mole part, and morepreferably in an amount of 0 mole part, based on 100 mole parts of thetotal of the polycarboxylic acid-derived structure unit and thepolyhydric alcohol-derived structure unit.

In the preparation of the polyester based resin (B12), a catalyst whichis different from a catalyst containing tin or antimony, particularly acatalyst containing titanium is preferably used. Examples of thecatalysts containing titanium include the aforementioned compounds.

Concrete product names of the aforementioned catalyst containingtitanium include, though is not restricted to, Orgatics TA-25(tetra-n-butyl titanate), TA-30 (tetra(2-ethylhexyl)titanate), TA-70(tetramethyl titanate) and the like as titanium alkoxide; Orgatics TPHS(polyhydroxy titanium stearate) and the like as titanium acylate; andOrgatics TC-401 (titanium tetra acetylacetonate), TC-200 (titaniumoctylene glycolate), TC-750 (titanium ethyl acetoacetate), TC-310(titanium lactate), TC-400 (titanium triethanol aminate) and the like astitanium chelate (all products are a product of Matsumoto ChemicalIndustry Co., Ltd.). The content of tin in the polyester based resin(B12) is not more than 5 ppm, preferably not more than 1 ppm, and morepreferably 0 ppm from the viewpoint of reduced environmental burdens.

As a resin contained in the resin microparticle (A) for a toner rawmaterial used in the present invention, a polyether polyol based resin(D) is preferable.

The polyether polyol based resin (D) used in the present invention alsoincludes modified resins thereof. The polyether polyol based resin (D)can be obtained by reacting at least one kind (E) selected frombisphenols (i), polyhydric alcohols (ii), and reactants (iii) of thepolyhydric alcohols and an acid anhydride, an epoxy resin (F), and acompound (G) having at least one active hydrogen in the molecule whichcan react with an epoxy group. In the preparation of the polyetherpolyol based resin (D), other components such as a crosslinking agent orthe like can be added. Examples of the modified resins of the polyetherpolyol based resins (D)include a urethane modified polyether polyolbased resin obtained by reacting a polyether polyol based resin and apolyisocyanate. The primary structure of these resins is notparticularly restricted. Any of a linear resin, a branched resin or acrosslinked resin can be used. Furthermore, by mixing several kinds ofpolyol based resins, the molecular weight, molecular weight distributionor thermal characteristics can be adjusted. Known styrene based resins,styrene-acrylic copolymerized resins, polyester based resins can also becontained as far as the characteristics are not damaged.

Concrete examples of bisphenols (i) include2,2-bis(4-hydroxyphenyl)propane [commonly called bisphenol A],bis(4-hydroxyphenyl)methane [commonly called bisphenol F],1,1-bis(4-hydroxyphenyl)ethane [commonly called bisphenol AD],1-phenyl-1,1-bis(4-hydroxyphenyl)methane,1-phenyl-1,1-bis(4-hydroxyphenyl)ethane and the like.

Examples of the polyhydric alcohols (ii) include the polyhydric alcoholsused as a raw material of the polyester based resin (B) or the like.

Examples of the acid anhydrides include phthalic anhydride, trimelliticanhydride, pyromellitic anhydride, ethylene glycol bistrimellitate,glycerol tristrimellitate, maleic anhydride, tetrahydrophthalicanhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylene tetrahydrophthalicanhydride, methylbutenyl tetrahydrophthalic anhydride, dodecenylsuccinic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalicanhydride, succinic anhydride, methylcyclohexene dicarboxylic anhydride,alkyl styrene-maleic anhydride copolymer, chlorendic anhydride,polyazelaic anhydride and the like.

The reaction of polyhydric alcohols and an acid anhydride can bepreferably carried out in the presence of a catalyst at 80° C. to 150°C. for 1 hour to 8 hours. The reaction of the polyhydric alcohols and anacid anhydride may be carried out during the polyaddition for producingthe resins or before the polyaddition. However, since an acid anhydridefunctions as a crosslinking agent and sometimes gelation takes place,the above reaction is more preferably carried out before thepolyaddition.

Examples of the catalyst used in the reaction include alkali metalhydroxides such as sodium hydroxide, potassium hydroxide, lithiumhydroxide and the like; alkali metal alcoholates such as sodiummethylate and the like; tertiary amines such as N,N-dimethylbenzylamine,triethylamine, pyridine and the like; quaternary ammonium salt such astetramethylammonium chloride, benzyltriethylammonium chloride and thelike; organic phosphorus compounds such as triphenylphosphine,triethylphosphine and the like; salts of alkali metals such as lithiumchloride, lithium bromide and the like; lewis acids such as borontrifluoride, aluminium chloride, tin (IV) chloride, tin2-ethylhexanoate, zinc benzoate and the like. The amount thereof ispreferably from 1 ppm to 1,000 ppm and more preferably from 5 ppm to 500ppm based on the amount of the product.

In the reaction, it is preferable that a solvent is not used from theviewpoint of a remained solvent. However, a solvent can also be used.Preferable examples of the solvents include aromatic hydrocarbons suchas toluene, xylene, ethylbenzene and the like; and ketones such asmethylisobutyl ketone, methylethyl ketone and the like.

Examples of epoxy resins (H)include a so-called one-step epoxy resinproduced from the above bisphenols and epichlorohydrin and a two-stepepoxy resin which is a product of an polyaddition of the one-step epoxyresin and bisphenols (page 30, [New Epoxy Resin] written by HiroshiKakiuchi (Shokodo Co., Ltd., 1986)). These epoxy resins may be usedsingly or in combination of two or more kinds. Also, a mixture incombination of two or more kinds having different number-averagemolecular weights may be used. When two or more kinds or a mixture incombination of two or more kinds having different number-averagemolecular weights are used, the ratio (Mw/Mn) of the weight-averagemolecular weight (Mw) to the number-average molecular weight (Mn)becomes greater, as compared to a case where a single kind is used, thusfavorably improving offset resistance. In that case, the number-averagemolecular weight of a low molecular weight component is preferably from300 to 3,000, while that of a high molecular weight component ispreferably from 3,000 to 10,000.

As the epoxy resin, epoxy resins obtained by replacing the partial orentire bisphenols by the above aromatic diols can also be used.

Examples of the compounds (G) having at least one active hydrogenreacting with an epoxy group in a molecule include monovalent phenols,secondary amine and monovalent carboxylic acids.

Examples of the monovalent phenols include phenol, cresol, isopropylphenol, octyl phenol, nonyl phenol, dodecyl phenol, xylenol, p-cumylphenol, a-naphthol, β-naphthol and the like.

Examples of the secondary amines include aliphatic secondary amines suchas diethylamine, dipropylamine, dibutylamine, dipentylamine,didodecylamine, distearylamine, diethanolamine, diallylamine and thelike; and aromatic ring-containing secondary amines such asN-methylanilin, N-methyltoluidine, N-methylnitroanilin, diphenylamine,ditolylamine, benzyldimethylamine and the like.

Examples of the monovalent carboxylic acids include aliphatic carboxylicacids such as propionic acid, butyric acid, caproic acid, caprylic acid,pelargonic acid, stearic acid and the like; aromatic ring-containingmonovalent carboxylic acid such as benzoic acid, toluic acid,α-naphthoic acid, β-naphthoic acid, phenyl acetate and the like.

Examples of the crosslinking agents include polyamines, acid anhydrides,trivalent or higher phenol compounds, trivalent or higher epoxy resinsand the like.

Examples of the polyamines include aromatic polyamine, aliphaticpolyamine and the like. Preferable examples thereof include diethylenetriamine, triethylene triamine, imino bispropylamine,bis(hexamethylene)triamine, trimethylhexamethylene diamine,diethylaminopropylamine, m-xylylenediamine, m-phenylenediamine,diaminodiphenylmethane, diaminodiphenylsulfone and the like.

As the acid anhydride, compounds such as the aforementioned acidanhydrides are preferable.

Examples of the trivalent or higher phenol compound include phenolnovolac resin, ortho-cresol novolak resin, 1,1,1-tris(4-hydroxyphenyl)methane,1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)propane,1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane,1-[α-methyl-α-(4-hydroxyphenyl)ethyl]-3-[α,α-bis(4hydroxyphenyl)ethyl]benzene,and1-[α-methyl-α-(4-hydroxyphenyl)ethyl]-4-[α,α-bis(4-hydroxyphenyl)ethyl]benzene.

The trivalent or higher epoxy resin is obtained, for example, by thereaction of a trivalent or higher phenol compound or a trivalent orhigher alcohol compound with epihalohydrine. Examples of the trivalentor higher phenol compounds include phenol novolac resin, ortho-cresolnovolak resin, 1,1,1-tris(4-hydroxyphenyl)methane,1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)propane, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane,1-[α-methyl-α-(4-hydroxyphenyl)ethyl]-3-[α,α-bis(4hydroxyphenyl)ethyl]benzene,1-[α-methyl-α-(4-hydroxyphenyl)ethyl]-4-[α,α-bis(4-hydroxyphenyl)ethyl]benzeneand the like. As the trivalent or higher alcohol, there can beexemplified, for example, 1,2,3,6-hexanetetrol, 1,4-sorbitan,pentaerythritol, dipentaerythritol, tripentaerythritol,1,2,4-butanetriol, glycerol, 2-methylpropanetriol,2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane,1,3,5-trihydroxymethylbenzene and the like.

The polyol based resin is preferably produced by an polyaddition of atleast one kind (E) selected from bisphenols (i), polyhydric alcohols(ii), reactants (iii) of the polyhydric alcohols and an acid anhydride,an epoxy resin (F), and a compound (G) having at least one activehydrogen in the molecule which can react with an epoxy group, andoptionally a crosslinking agent. In that polyaddition, the amount of theactive hydrogen group capable of reacting with an epoxy group ispreferably from 0.5 mole equivalent to 2.0 mole equivalents, and furtherpreferably from 0.7 mole equivalent to 1.5 mole equivalent based on 1mole equivalent of the epoxy group in the system. The amount of lessthan 0.5 is not preferable because gelation may occur in the system andthe reaction may be difficult to control in some cases The amount ofgreater than 2.0 is not preferable because a lot of the monomers remainsat the end of the reaction. The polyol based resin can be produced, forexample, by using bisphenol A in an amount of from 0.01 mole to 3 mole,benzoic acid in an amount of from 0.005 mole to 2 mole, stearic acid inan amount of from 0 mole to 0.2 mole, and a reactant of propylene oxideadducts of bisphenol A and phthalic anhydride in an amount of from 0mole to 1 mole, as compounds having an active hydrogen in the moleculewhich can react with an epoxy group, based on 2 mole to 3.5 mole of anepoxy resin.

In the preparation of the polyether polyol based resin (D) of thepresent invention, the polyaddition may be carried out by using acatalyst. Examples of the catalysts include the catalysts which can beused for the reaction of the polyhydric alcohol and acid anhydride. Whena catalyst is used in the preparation of the resin of the presentinvention, the amount is usually from 1 ppm to 1,000 ppm and preferablyfrom 5 ppm to 500 ppm based on the amount of a product.

In the polyaddition for producing the polyol based resin of the presentinvention, it is preferred that a solvent is not used from the viewpointof a remained solvent. However, a solvent can also be used. Preferableexamples of the solvent include aromatic compounds such as toluene,xylene and the like; and ketones such as 2-butanone, methylisobutylketone, cyclohexanone and the like; ethers such as ethylene glycoldibutyl ether, diethylene glycol dimethyl ether, tetrahydrofuran,dioxane, anisole and like; and aprotic polar solvents such asN,N-dimethylformamide, dimethylsulfoxide, 1-methyl-2-pyrrolidone and thelike. These solvents can also be used singly or in combination of two ormore kinds. In the case of using the solvent, the amount thereof isusually in a proportion of from 1 mass % to 100 mass % and preferablyfrom 5 mass % to 50 mass % of the mass of the raw material to be fed.

The reaction temperature in the polyaddition is different depending onthe based or the amount of a catalyst, but it is preferably in the rangeof 120° C. to 200° C. When the reaction temperature is higher than 200°C., some kinds of catalysts may lose their activities and the resin maybe colored remarkably in some cases.

Generally, the reaction can be traced by the epoxy equivalent, softeningpoint, gel permeation chromatography (GPC) or the like. In the presentinvention, the end point of the reaction is preferably determined by thepoint where the epoxy group disappears substantially, that is, the epoxyequivalent becomes not less than 20,000 g/Eq. In the present invention,the epoxy equivalent refers to the mass (g) of an epoxy resin per 1 gequivalent of an epoxy group.

In the polyol based resin of the present invention, a number-averagemolecular weight (Mn) is preferably in the range of 1,000 to 20,000,more preferably in the range of 1,500 to 15,000, and particularlypreferably in the range of 2,500 to 5,000. When Mn is less than 1,000,the resin strength and cohesive force of the resin may be deterioratedso that sufficient durability and offset resistance are not exhibited insome cases. When Mn exceeds 20,000, sufficient fixing properties orgloss may not be shown in some cases. Mw/Mn is preferably from 5 to 50and particularly preferably from 10 to 35. Mw/Mn of less than 5 is notpreferable because sufficient offset resistance may not be exhibited.Mw/Mn of more than 50 is not preferable because the high viscosity inthe system in the preparation make it difficult to control the reaction.

The softening point is preferably from 85° C. to 150° C. andparticularly preferably from 100° C. to 135° C. The softening pointmentioned herein is a softening temperature of a sample measured at aheating rate of 1° C./min using a softening point measuring device(FP90, a product of Mettler Toledo K. K.). When the softening point isless than 85° C., it is not preferable from the viewpoint of durability.When the softening point exceeds 135° C., sufficient fixing propertiesor gloss may not be exhibited in some cases.

A glass transition temperature (Tg) is preferably from 50° C. to 90° C.and particularly preferably from 55° C. to 70° C. from the viewpoints ofsecuring fixing properties, offset resistance and anti-blockingproperties.

A hydroxyl value of the polyol based resin used in the present inventionis preferably from 100 KOHmg/g to 300 KOHmg/g and more preferably from150 KOHmg/g to 250 KOHmg/g. By achieving the structure having aplurality of hydroxyl groups on a molecular chain, the cohesive force ofa resin is increased due to an inter-molecular hydrogen binding force,thus even a resin having a relatively small molecular weight can exhibitsuperior performance with regard to development durability. In thepresent invention, the hydroxyl value refers to mg of potassiumhydroxide necessary to neutralize an acid anhydride necessary toesterify the hydroxyl group present in 1 g of the resin.

A urethane modified polyol based resin obtained by chain-extending ofpolyol based resin using a polyisocyanate is preferably used from theviewpoint of the good offset resistance.

In that case, the polyisocyanate is preferably used in an amount of notmore than 0.5 mole equivalent and more preferably not more than 0.3 moleequivalent of an isocyanate group per 1 mole equivalent of the hydroxylgroup of the polyol based resin. When it is not less than 0.5 moleequivalent, sufficient fixing properties are not obtained in some cases.

Examples of the polyisocyanates include compounds such as theaforementioned polyisocyanate (b).

Preferred examples of methods for reacting the polyol based resin with apolyisocyanate include a method comprising feeding the polyol basedresin into a twin screw extruder for kneading, and then feeding thepolyisocyanate into the resin mixture during kneading and conveying forfurther melt-kneading. Examples of reactors used in the other methodthan those above include a single screw extruder, a static mixer and ausual reactor with a stirrer.

The preferred range of the reaction temperature is the same as thetemperature range in the aforementioned reaction of the polyester resin(a) and the polyisocyanate (b).

In the present invention, in the preparation of an aqueous dispersedsystem comprising the resin microparticle (A) for a toner raw materialdispersed in water, a emulsifying auxiliary may be used along with theresin.

The emulsifying auxiliary in the present invention promotes theformation of an aqueous dispersed system. Any known emulsifyingauxiliaries can be used without restrictions.

Preferred Examples of the emulsifying auxiliaries include a sulfonicacid group-containing polyester based resin, a sulfonic acidgroup-containing vinyl copolymer and their metal salts and theirammonium salts. In addition, thermoplastic resins swollen or dissolvedin water such as polyvinyl alcohol, partly saponified polyvinyl alcohol,methylcellulose, carboxymethylcellulose or sodium salts thereof are alsopreferable. In the present invention, in particular, a sulfonic acidgroup-containing polyester based resin is suitably used as theemulsifying auxiliary. A sulfonic acid group-containing monomer ispreferably contained in an amount of from 3 mole % to 35 mole % based onthe total acid components of the sulfonic acid group-containingpolyester resin. Several kinds of the above emulsifying auxiliarys maybe used in combination.

Examples of the sulfonic acid group-containing monomers as a rawmaterial of the sulfonic acid group-containing polyester based resininclude the aforementioned ones. Among these, aromatic dicarboxylic acidmetal salts containing a sulfonic acid group is suitably used. Theamount thereof is not particularly restricted, but it is preferably notmore than 35 mole % and more preferably not more than 25 mole % of thetotal acid components of a raw material of the sulfonic acidgroup-containing polyester based resin. Within the above range, waterabsorption of a toner can be prevented and a toner with excellentelectrification stability can be obtained.

As a raw material of the sulfonic acid group-containing polyester basedresin, those described above are preferably used.

Tg of the sulfonic acid group-containing polyester based resin and anumber-average molecular weight (Mn) of the tetrahydrofuran (THF)soluble component are preferably those as described above.

As other emulsifying auxiliaries anionic surfactants may be used.Examples of the anionic surfactants include anionic surfactants obtainedby reacting with basic substances, such as primary higher fatty acidsalts, secondary higher fatty acid salt, primary higher alcohol sulfateester salts, secondary higher alcohol sulfate ester salts, higher alkyldisulfonic acid salts, sulfonated higher fatty acid salts, higher fattyacid sulfate ester salts, higher fatty acid ester sulfonic acid salts,sulfate ester salts of higher alcohol ether, sulfonic acid salts ofhigher alcohol ether, alkyroled sulfate ester salts of higher fatty acidamide, alkylbenzene sulfonic acid salts, alkylphenol sulfonic acidsalts, alkylnaphthalene sulfonic acid salts, alkylbenzoimidazolesulfonic acid salts and the like. More concrete compound names of thesesurfactants are disclosed, for example, in “Synthetic Surfactant”written by Hiroshi Horiguchi (published by Sankyo Publishing, 1966).

Hereinafter, the toner using the resin microparticle (A) for a toner rawmaterial of the present invention will be illustrated in detail.

To produce the toner of the present invention, a method comprisingforming an aggregate of the resin microparticle (A) for a toner rawmaterial and thermally fusing the aggregate is suitably used.

To form the aggregate of the resin microparticle (A) for a toner rawmaterial, conventionally known methods for forming an aggregate can beused without restrictions. As a preferred example, an aggregate isformed by adding water-soluble salts of an alkali metal, an alkali earthmetal or aluminium, such as magnesium sulfate, aluminium sulfate, bariumchloride, magnesium chloride, calcium chloride, sodium chloride and thelike dissolved in water as a coagulant. Further, an aggregate is formedby adding an ionic surfactant as a coagulant. Examples of the abovesurfactants include alkylbenzene dimethyl ammonium chloride, alkyltrimethyl ammonium chloride, distearyl ammonium chloride and the like.

To form an aggregate in a method for producing the toner of the presentinvention, in addition to a dispersed system with the resinmicroparticle for a toner of the present invention dispersed therein, adispersed system with a releasing agent dispersed therein, a dispersedsystem with a colorant dispersed therein, a dispersed system with amagnetic powder dispersed therein or the like may be used. In that case,the aforementioned method for forming an aggregate can also be applied.As other methods for forming an aggregate, an aggregate is also formedby charging at least one kind of a dispersed system of a dispersedsystem with resin microparticle for a toner dispersed therein, adispersed system with a releasing agent dispersed therein, a dispersedsystem with a colorant dispersed therein and a dispersed system with amagnetic powder dispersed therein reversely with respect to the other,and then mixing them. Further, these aggregation processes can be usedtogether.

In the present invention, in the case of forming the above aggregate,the aggregate may be formed by multistage process for the purpose ofcontrolling the toner surface structure. For example, after forming anaggregate of a resin microparticle for a toner, a releasing agent and acolorant,, a dispersed system with the resin microparticle for a tonerof the present invention dispersed therein or a dispersed systemcomprising other known binder resins or a binder resin and a emulsifyingauxiliary is added subsequently for attaching to the aggregate surfacein order to prevent a releasing agent or a colorant from being exposedto the toner surface. In that case, a dispersed system with a knownbinder resin such as a styrene-acrylic binder resin, a polyol basedbinder resin or the like can also be post-added for attaching to theaggregate surface for controlling the surface.

The above aggregate is preferably subjected to thermal fusion forenhancing stability as a particle. The thermal fusion is preferablycarried out at not less than a glass transition temperature or a meltingpoint of the resin constituting the aggregate, and not more than athermal decomposition temperature of the resin, for 30 minutes to 10hours according to the target toner shape. Concretely, the temperatureis preferably from 40° C. to 180° C. and more preferably from 50° C. to1 40° C. The thermal fusion can be carried out using a known heatingdevice or apparatus.

In the production method of the toner of the present invention, as thereleasing agent, a known releasing agent having a melting point of from70° C. to 155° C. can be preferably used. Concrete examples thereofinclude polyolefins having a low molecular weight such as polyethylene,polypropylene, polybutene and the like; silicones having a softeningpoint by heating; aliphatic amides such as oleamide, erucamide,ricinoleamide, stearylamide and the like; or natural waxes such asceramic wax, rice wax, sugar wax, urushi wax, beeswax, carnauba wax,candelilla wax, montan wax and the like; a Fisher-Tropsch wax, modifiedmaterials thereof and the like. These releasing agents are dispersed inwater with an ionic surfactant or a polymer electrolyte such as polymeracid, polymer base and the like, heated to not less than the meltingpoint, and treated using a homogenizer or a pressure discharge typedispersing machine which is capable of applying a strong shearing force,whereby a dispersed system with a releasing agent having a diameter ofnot more than 1 μm dispersed therein can be obtained.

In the method for producing the toner of the present invention, knowndyes and pigments can be used for colorants. Concrete examples thereofinclude carbon black, magnetite, Phthalocyanine Blue, Peacock blue,Permanent red, lake red, Rhodamine lake, Hansa Yellow, Permanent yellow,benzidine yellow, oil black, azo oil black or the like. More concreteexamples thereof include nigrosine dyes (C. I. No. 50415), aniline blue(C. I. No. 50405), charcoal blue (C. I. No. azoec Blue 3), chrome yellow(C. I. No. 14090), ultra marine blue (C. I. No.77103), Dupont oil red(C. I. No.26105), Orient oil red # 330 (C. I. No. 60505), QuinolineYellow (C. I. No.47005), methylene blue chloride (C. I. No. 52015),Phthalocyanine Blue (C. I. No. 74160), Malachite Green oxalate (C. I.No. 42000), lamp black (C. I. No. 77266), rose Bengal (C. I. No. 45435)or the like. In the present invention, a surface-treated colorantobtained by polymerizing a polymerizable monomer in the presence of acolorant can also be used. An aqueous dispersed system of a colorant isobtained, for example, by mixing a colorant and a surfactant, anddispersing the mixture in water according to a known method.

In the method for producing the toner of the present invention, as acharge controlling agent, any known charge controlling agents can beused. Specifically, known charge controlling agents such asnigrosine-based dyes, triphenyl methane-based dyes, quaternary ammoniumsalt, amine compounds or imine compounds, metal salicylate compounds,metal alkylsalicylate compounds or metal-containing azo dyes can besuitably selected and used accordingly. However, they are preferablyhardly dissolved in water from the viewpoint of ionic strength orcontamination by waste water.

In the method for producing the toner of the present invention, examplesof the magnetic powders include metals such as ferrite, magnetite,reduced iron, cobalt, nickel, manganese and the like, alloys, orcompounds comprising these metals.

The compound ratio of a component for toner in the formation of a toneraggregate of the present invention is described below when the totalmass of the resin microparticle (A) for a toner raw material of thepresent invention, a colorant, a charge controlling agent and areleasing agent is 100 mass %. The content of the resin microparticle(A) for a toner raw material of the present invention is from 50 mass %to 99 mass % and more preferably from 60 mass % to 95 mass %. Thecontent of the colorant is preferably from 1 mass % to 25 mass % andmore preferably from 1 mass % to 15 mass % from the viewpoint oftransparency. Further, the content of the charge controlling agent isusually preferably from 0 mass % to 10 mass %. Further, the content ofthe releasing agent is preferably from 0 mass % to 20 mass % and morepreferably from 0 mass % to 15 mass %. When the amount of the releasingagent is within the above range, the toner has good storage stability.Further, in the present invention, other components than the colorant,charge controlling agent, releasing agent, for example, magnetic powderor the like can be compounded as far as the effect of the presentinvention is not damaged.

In the present invention, for the purpose of enhancing dispersability toa toner, a colorant, a releasing agent or a charge controlling agent maybe added in the preparation of the resin microparticle (A) for a tonerraw material of the present invention. The amount thereof is the same asthe compound ratio of the component for a toner in the formation of anaggregate.

As described above, a particle obtained via the formation of the resinmicroparticle (A) for a toner raw material, the formation of anaggregate, a thermal fusion process and proper processes such aswashing, drying or the like can be suitably used as a toner.

By adding the surface-treating agent to the surface of the obtainedtoner for electrostatic development the surface-treating agent existsbetween the toners and carriers or between the toners. Thus, the powderfluidity and the life of developing agent can be improved. Specificexamples of the surface-treating agent include fine powders such ascolloidal silica, alumina, titanium oxide, polytetrafluoroethylene,polyvinylidene chloride, polymethyl methacrylate, polystyrene ultrafineparticles and silicone. Examples of commercial products include AEROSIL130, 200, 200V, 200CF, 200FAD, 300, 300CF, 380, R972, R972V, R972CF,R974, R976, RX200, R200, R202, R805, R812, R812S, TT600, MOX80, MOX170,COK84, titanium oxide T805 and titanium oxide P25 (these are products ofNippon Aerosil Co., Ltd. and Degussa Japan Co., Ltd.); and CAB-O-SILL90, LM130, LM150, M5, PTG, MS55, H5, HS5, LM150D, M7D, MS75D, TS720,TS610 and TS530 (these are products of CABOT Corp.). The specificsurface area of the surface-treating agent is preferably not less than30 m²/g, and particularly in the range of 50 m²/g to 400 m²/g asmeasured by nitrogen adsorption by the BET method. The amount of thesurface-treating agent added is preferably from 0.1 mass part to 20 massparts per 100 mass parts of the toner.

The toner obtained by the present invention can be applied to variousfixing methods such as a so-called oil-free fixing method, an oil-coatedheat roll fixing method, a flash fixing method, an oven fixing method,and a pressure fixing method. The toner according to the presentinvention can be applied to various cleaning methods, for example, aso-called fur brush method, a blade method or the like. It can also beapplied to the image formation method omitting a cleaning process.

EXAMPLES

The present invention is now more specifically illustrated below withreference to Examples and Comparative Examples. Measuring methods fordata in each Table are as follows.

(Glass Transition Temperature)

A glass transition temperature in the present invention was measured inaccordance with JIS K-7121.

(Acid Value)

In the present invention the acid value was measured by theneutralization titrimetric method. 5 g of the sample was dissolved in 50ml of a mixed solvent of xylene/dimethyl formamide =1/1 (mass ratio) andseveral droplets of a phenolphthalane/ethanol solution were addedthereto as an indicator and then the resulting mixture was titrated witha 0.1 normal KOH aqueous solution. The acid value (KOHmg/g) wascalculated from the titration amount and sample mass at the end pointwhere the color of the sample solution was painted from colorlessness topurple.

(Hydroxyl Value)

In the present invention, the hydroxyl value was measured by the backtitration with the acid anhydride. 500 ml of pyridine, 70 g of phthalateand 10 g of imidazole were mixed to prepare a phthalized reagent. 5 mlof the phthalized reagent was added to 2g of a resin and dissolvedtherein. Then, the resulting solution was allowed to stand at 100° C.for 1 hour. After that, 1 ml of water, 70 ml of tetrahydrofuran andseveral droplets of a phenolphthalane-ethanol solution were added to theresin solution and then the resulting mixture was titrated with a 0.4normal NaOH aqueous solution. The hydroxyl value (KOHmg/g) wascalculated from the titration amount and sample mass at the end pointwhere the color of the sample solution was painted from colorlessness topurple.

(Quantitative Analysis of Metals)

In the present invention, quantitative analysis of metals in the resinwas performed using an inductively coupled plasma atomic emissionspectrometer SPS1200A (a product of Seiko Instruments Inc.).

(Analysis of Content of Bisphenol A-Derived Structure Unit)

In the present invention, the content of the bisphenol A-derivedstructure unit in the resin was determined by NMR measurement of thehydrolyzed sample.

(Amount of THF Insoluble Component)

In the present invention, the amount of the THF insoluble component wasdetermined according to the following method. A solution of about 5 mass% was prepared by using a resin of about 2.5 g and THF of about 47.5 g.Hereinafter, the concentration of the solution is referred to as “RC.”RC was obtained from an precise weighing value of the resin mass and THFmass. Then, the above solution was stirred at 25±3° C. for 12 hours todissolve the soluble component of the resin completely. Subsequently,the obtained solution was allowed to stand for 16 hours. After theseparation of the insoluble component and the supernatant liquid, 5 g ofthe supernatant liquid was collected and weighed precisely. Then,thesolution was dried at 150° C. for an hour and the mass of remainingresin was measured. From these values, the concentration of thesupernatant liquid “SC” was calculated.

The amount of the THF insoluble component was determined by thefollowing formula from the values of RC and SC.

The ratio of THF insoluble component=[(RC−SC)/RC]×100 (%)

In the case of measuring the resin microparticle for a toner rawmaterial, the sample obtained by drying an aqueous dispersed system ofthe resin microparticle at 150° C. for 2 hours and then cooling andsolidifying was measured.

(Polyisocyanate-derived Structure and Vinyl Copolymer-derived Structure)

In the present invention, existence of a polyisocyanate-derivedstructure in the THF insoluble component and a vinyl copolymer in theresin microparticle for a toner was confirmed by IR measurement.

(Molecular Weight)

The molecular weight was determined using the gel permeationchromatography (GPC). The measurement was conducted under the followingconditions, based on the commercially available monodispersed standardpolystyrene.

-   -   Detector: SHODEX RI-71S (Refractometer, a product of Showa Denko        K.K.)    -   Mobile phase: Tetrahydrofuran    -   Column: A piece of KF-G, three pieces of KF-807L and a piece of        KF800D, manufactured by Showa Denko K.K., were connected        serially.    -   Flowrate: 1.0 ml/min    -   Sample: 0.25% THF solution

I The reliability of the measurement was confirmed by checking whetherMw/Mn of NBS706 polystyrene sample (Mw=288,000, Mn=137,000, andMw/Mn=2.11)measured under the above condition is 2.11±0.10 or not.

(Particle Diameter of Resin Microparticle as Raw Material for Toner)

An average particle diameter of 50% volume (D50), a particle diameter of10% volume (D10) and a particle diameter of 90% volume (D90) weremeasured using Microtrac HRA (a product of Microtrac Inc.).

(Particle Diameter of Toner)

A particle diameter of 50% volume of the toner was measured using acoulter counter.

(Content of Organic Solvent)

2 mass parts of 2-paropanol was added to 1 weight part of a toner as ameasuring object. The mixture was dispersed using an ultrasonic wave for30 minutes and kept in a refrigerator (5° C.) for I day or more forextracting the solvent in the toner. The supernatant liquid was analyzedusing the gas chromatography to weigh the amount of a solvent in thetoner. In the case of the microparticle for a toner raw material, ahigh-density emulsified product obtained using a twin screw extruder wasused for the measurement.

-   -   Device: Shimadzu GC-14A    -   Column: CBP20-M 50-0.25    -   Detector: FID    -   Injected amount: 1 to 5 μm    -   Carrier gas: He 2.5 kg/cm²    -   Hydrogen flow rate: 0.6 kg/cm²    -   Air flow rate: 0.5 kg/cm²    -   Chart speed: 5 mm/min    -   Sensitivity: Range 101×Atten 20    -   Column temperature: 40° C.    -   Injection temperature: 150° C.

(Preparation of Resin)

An example using a polyester resin is illustrated.

Resin (A-1-1)

A 5-liter, 4-necked flask was provided with a reflux condenser, awater-separating unit, a nitrogen gas inlet tube, a thermometer and astirrer. Thereinto were fed 24.0 mole of ACTCOL KB300 (bisphenol Aderivative, a product of Mitsui Takeda Chemicals, Inc.), 56.0 mole ofethylene glycol (EG), 10.0 mole of trimethylolpropane (TMP), 4.0 mole oftriethylene glycol (TEG), 83.5 mole % of terephthalic acid (TPA) and18.3 mole of benzoic acid (Benz A). Dehydration and polycondensationwere conducted at 180° C. to 240° C. with nitrogen being introduced intothe flask to obtain a resin (A-1-1). The physical properties of theresin were shown in Table 1.

Resin (A-1-2) to Resin (A-1-4)

Resins (A-1-2) to (A-1-4) were produced in the same manner as in thepreparation of the resin (A-1-1), except that the raw materialcompositions were changed to the contents in Table 1. The physicalproperties thereof were shown in Table 1. TABLE 1 Resin A-1-1 A-1-2A-1-3 A-1-4 Raw KB-300 24 28.5 24 0 material TMP 10 5 12 0 (mole EG 5666.5 56 66 part) DEG 0 0 0 24 TEG 4 0 8 10 TPA 83.5 96.5 85 60 Benz A18.3 25.5 0 0 IPA 0 0 0 20 5-sulfoisophthalic 0 0 0 10 acid Physical Tg(° C.) 45 51 36.6 49.4 properties Hydroxyl value 22 3 87.8 6.5 (KOHmg/g)Acid value 2.1 24.7 12.8 2.5 (KOHmg/g) Mn 2,800 2,400 1,830 2,400 Mw15,600 6,000 6,330 55,000KB-300: Bisphenol A derivativeTMP: trimethylolpropaneEG: ethylene glycolDEG: diethylene glycolTEG: triethylene glycolTPA: terephthalic acidBenz A: benzoic acidIPA: isophthalic acid

Resin (A-2-1)

A mixture of 70 mass parts of the resin (A-1-1) and 30 mass parts of theresin (A-1-4) was fed into a twin screw extruder at a flow rate of 10kg/hr for kneading at 175° C. and 3.0 mass parts of tolylenediisocyanate (TDI) was further fed into the resin mixture duringkneading and conveying the resin mixture for further kneading to obtaina resin (A-2-1). Tg of the obtained resin was shown in Table 2.

Resin (A-2-2) to Resin (A-2-3)

Resins (A-2-2) and (A-2-3) were produced in the same manner as in thepreparation of the resin (A-2-1), except that the raw materialcompositions were changed to the contents in Table 2. Tg thereof werealso shown in Table 2. TABLE 2 Resin A-2-1 A-2-2 A-2-3 Raw materialresin A-1-1 70 A-1-2 55 A-1-2 70 (mass part) A-1-4 30 A-1-3 15 A-1-3 30A-1-4 30 TDI (mass part) 3 2.4 2.1 Tg (° C.) 62 52 54

Resin (b1-1)

A 5-liter, 4-necked flask was provided with a reflux condenser, awater-separating unit, a nitrogen gas inlet tube, a thermometer and astirrer. Thereinto were fed at a ratio of 12.8 mole parts of ACTCOLKB300, 30.0 mole parts of EG, 2.3 mole parts of TMP, 43.5 mole parts ofTPA and 11.5 mole parts of Benz A. Dibutyltin oxide was added in anamount of 0.3 mass % based on the total mass of monomers. Dehydrationand polycondensation were conducted at 180° C. to 240° C. with nitrogenbeing introduced into the flask to obtain a resin (b1-1).

The physical properties of the resin were shown in Table 3.

Resin (b1-2) to Resin (b1-3)

Resins (b1-2) and (b1-3) were produced in the same manner as in thepreparation of the resin (b1-1), except that the raw materialcompositions were changed to the contents in Table 3. The physicalproperties thereof were also shown in Table 3.

Resin (b1-4)

A 5-liter, 4-necked flask was provided with a reflux condenser, a 5water-separating unit, a nitrogen gas inlet tube, a thermometer and astirrer. Thereinto were fed 4.2 mole parts of sodium dimethyl5-sulfoisophthalic acid and 30.5 mole parts of EG. 0.2 mass part oftitanium lactate (Orgatics TC-310, a product of Matsumoto ChemicalIndustry Co., Ltd.) was added thereto for carrying out demethanolationat 180° C. to 220° C. and then 13.7 mole parts of DEG, 6.3 mole parts ofTEG, 31.6 mole parts of TPA and 13.7 mole parts of IPA were fedthereinto. Dehydration and polycondensation were conducted at 180° C. to240° C. with nitrogen being introduced into the flask to obtain a resin(b1-4). The physical properties of the resin (b1-4) were shown in Table3. TABLE 3 Resin b1-1 b1-2 b1-3 b1-4 Raw material KB-300 12.8 13.2 13 0(mole part) Sodium dimethyl 0 0 0 4.2 5-sulfoisohthalic acid EG 30 30.830.3 30.5 DEG 0 0 0 13.7 TEG 0 0 4.3 6.3 TMP 2.3 2.3 6.5 0 TPA 43.5 47.245.9 31.6 Benz A 11.5 6.5 0 0 IPA 0 0 0 13.7 Physical Tg (° C.) 53 61 3750 properties Hydroxyl value 4.3 3 87.8 3.5 (KOHmg/g) Acid value 22.3 2812.8 2.8 (KOHmg/g) Mn 1,500 3,400 1,800 2,500 Mw 5,900 9,500 6,30054,000 Peak molecular 5,300 7,000 5,000 9,800 weight

Resin (b2-1)

40.0 mass parts of xylene was fed into a 5-liter flask purged withnitrogen and heated by an oil bath. Under reflux (internal temperature:138° C.), a mixture of 78.0 mass parts of styrene, 20.0 mass parts ofn-butyl acrylate, 2.0 mass parts of glycidyl methacrylate (correspondingto 2.6 mole parts when the total of all vinyl monomers was 100 moleparts) and 0.5 mass part of di-t-butylperoxide was continuously droppedthereto over 5 hours. Then, the resulting mixture was further reactedfor an hour for polymerization. After that, with maintaining theinternal temperature at 130° C., 0.5 mass part of di-t-butylperoxide wasadded thereto and the reaction was carried out for 2 hours 10 tocomplete the polymerization. The obtained resin was flashed at 190° C.in a vessel under 10 mmHg for removing the solvent to obtain a resin(b2-1). The physical properties of the resin (b2-1) were shown in Table4.

Resin (b2-2)

A resin (b2-2) was produced in the same manner as in the preparation ofthe resin (b2-1), except that the raw material compositions were changedto the contents in Table 4. The physical properties thereof were alsoshown in Table 4. TABLE 4 Resin b2-1 b2-2 Raw material Styrene 78 75(mass part) n-butyl acrylate 20 17 Glycidyl methacrylate 2 8 Glycidylmethacrylate (mole part) 2.6 10.2 Physical Tg (° C.) 57 61 properties Mn8,500 6,000

Glycidyl methacrylate (mole part): moles of glycidyl methacrylate basedon 100 moles of all vinyl monomers.

Resin (b3-1)

A 5-liter, 4-necked flask was provided with a reflux condenser, awater-separating unit, a nitrogen gas inlet tube, a thermometer and astirrer. Thereinto were fed 14.5 mole parts of NPG, 33.7 mole parts ofEG, 33.7 mole parts of TPA, 15.2 mole parts of IPA and 2.9 mole parts ofBenz A. 0.2 mass % of titanium lactate (Orgatics TC-310, a product ofMatsumoto Chemical Industry Co., Ltd.) based on the total mass ofmonomers was added thereto. Dehydration and polycondensation wereconducted at 180° C. to 240° C. with nitrogen being introduced into theflask to obtain a resin (b3-1). The physical properties of the resinwere shown in Table 5.

Resin (b3-2) to Resin (b3-3)

Resins (b3-2) and (b3-3) were produced in the same manner as in thepreparation of the resin (b3-1), except that the raw materialcompositions were changed to the contents in Table 5. The physicalproperties thereof were also shown in Table 5.

Resin (b3-4)

A 5-liter, 4-necked flask was provided with a reflux condenser, awater-separating unit, a nitrogen gas inlet tube, a thermometer and astirrer. Thereinto were fed 1.4 mole part of sodium dimethyl5-sulfoisophthalic acid and 14.5 mole parts of NPG. 0.2 mass % oftitanium lactate (Orgatics TC-310, a product of Matsumoto ChemicalIndustry Co., Ltd.) based on the total mass of monomers was addedthereto for carrying out demethanolation at 180° C. to 220° C. Then,33.7 mole parts of EG, 33.7 mole parts of TPA, 13.7 mole parts of IPAand 2.9 mole parts of Benz A were fed thereinto. Dehydration andpolycondensation were conducted at 180° C. to 240° C. with nitrogenbeing introduced into the flask to obtain a resin (b3-4). The physicalproperties of the resin (b3-4) were shown in Table 5.

Resin (b3-5)

A resin (b3-5) was produced in the same manner as in the preparation ofthe resin (b3-4), except that the raw material compositions were changedto the contents in Table 5. The physical properties thereof were alsoshown in Table 5. TABLE 5 Resin b3-1 b3-2 b3-3 b3-4 b3-5 Raw materialSodium dimethyl 0 0 0 1.4 4.8 (mass part) 5-sulfoisophthalic acid NPG14.5 13.3 13.6 14.5 14.5 EG 33.7 31 31.7 33.7 33.7 TEG 0 0 4.5 0 0 TMP 02.3 3.6 0 0 TPA 33.7 46.5 46.6 33.7 33.7 IPA 15.2 0 0 13.7 10.4 Benz A2.9 7 2.9 2.9 Physical Tg (° C.) 57 54 45 56 63 properties Hydroxylvalue 2.4 5 60.2 2.5 1.5 (KOHmg/g) Acid value 25.4 26 8.2 30 32(KOHmg/g) Mn 2,600 2,600 3,900 2,300 2,100 Mw 6,400 10,000 16,400 6,0005,800 Peak molecular 6,500 6,300 8,000 6,100 5,900 weight

Resin (B1-1)

53 mass parts of the resin (b1-1), 17 mass parts of the resin (b1-3) and30 mass parts of the resin (b1-4) were mixed. The resulting mixturecontains 1.4 mole % of a structure unit having a sulfonic acid group inthe total of the polycarboxylic acid-derived structure unit and thepolyhydric alcohol-derived structure unit constituting the polyesterbased resin (B). The mixture was fed into a twin screw extruder at aflow rate of 10 kg/hr for kneading at 175° C., and 4.1 mass parts oftolylene diisocyanate (TDI) was fed into the resin mixture duringkneading and conveying the resin mixture for further kneading to obtaina resin (B1-1). The physical properties of the resin were shown in Table6.

Resin (B1-2) to Resin (B1-5)

Resins (B1-2) to (B1-5) were produced in the same manner as in thepreparation of the resin (B1-1), except that the raw materialcompositions were changed to the contents in Table 6. The physicalproperties thereof were also shown in Table 6. TABLE 6 Resin B1-1 B1-2B1-3 B1-4 B1-5 Raw material resin b1-1 53 b1-2 53 b1-1 60 b1-1 45 b1-170 (mass part) b1-3 17 b1-3 17 b1-3 20 b1-3 15 b1-3 30 b1-4 30 b1-4 30b1-4 20 b1-4 40 TDI (mass part) 4.1 4.3 3.9 2.5 2.5 Sulfonic acid group1.4 1.4 1 1.9 0 (mole %) Polyisocyanate-derived Yes Yes Yes Yes Yesstructure Physical Tg (° C.) 55.1 58.5 57.6 53.6 54.4 properties THF 6.89 4.3 3.5 3 insoluble component (mass %) Peak 5,500 7,100 5,400 5,6005,300 molecular weight

Sulfonic acid group (mole %): The ratio of a structure unit having asulfonic acid group in the total of a polycarboxylic acid-derivedstructure unit and a polyhydric alcohol-derived structure unitconstituting a polyester based resin.

Polyisocyanate-derived structure: Existence of a polyisocyanate-derivedstructure in the THF insoluble component.

Peak molecular weight: Peak molecular weight of the THF solublecomponent.

Resin (B2-1)

53 mass parts of the resin (b1-1), 14 mass parts of the resin (b1-3) and30 mass parts of the resin (b1-4) were mixed to prepare a mixture. Themixture contains 1.5 mole % of a structure unit having a sulfonic acidgroup and/or a sulfonic acid metal salt group in the total of thepolycarboxylic acid-derived structure unit and the polyhydricalcohol-derived structure unit constituting polyester. Thereto was mixed3 mass parts of the resin (b2-1). The resulting mixture was fed into atwin screw extruder at a flow rate of 10 kg/hr for kneading at 175° C.,and 4.3 mass parts of TDI was fed into the resin mixture during kneadingand conveying the resin mixture for further kneading to obtain a resin(B2-1). The resin (B2-1) contains 3 mass % of a vinyl copolymer. Tg ofthe obtained resin was 56.0° C. and the THF insoluble component was 7.1mass %. By IR a polyisocyanate-derived structure was confirmed in theTHF insoluble component, and a vinyl copolymer was further confirmed inthe resin. The peak molecular weight of the THF soluble component was5,400.

Resin (B2-2) to Resin (B2-4)

Resins (B2-2) to (B2-4) were produced in the same manner as in thepreparation of the resin (B2-1), except that the raw materialcompositions were changed to the contents in Table 7. The physicalproperties thereof were also shown in Table 7. TABLE 7 Resin B2-1 B2-2B2-3 B2-4 Raw material resin (mass part) b1-1 53 b1-1 51 b1-1 53 b3-1 53b1-3 14 b1-3 14 b1-3 14 b3-3 14 b1-4 30 b1-4 29 b1-4 30 b3-5 30 b2-1 3b2-1 6 b2-2 3 b2-1 3 TD (mass part) 4.3 4.3 4.3 2.1 Content of sulfonicacid group 1.5 1.5 1.5 1.5 (mole %) Content of vinyl copolymer 3 6 3 3(mass %) Polyisocyanate-derived structure Yes Yes Yes Yes Physical Tg (°C.) 56 56.3 55.8 61 properties THF insoluble 7.1 7.4 7.9 7.1 component(mass %) Peak molecular 5,400 5,500 5,500 6,200 weight

Content of vinyl copolymer (mass %): Content of a vinylcopolymer-derived structure in a polyester based resin.

Resin (B3-1)

53 mass parts of the resin (b3-1), 17 mass parts of the resin (b3-3) and30 mass parts of the resin (b1-4) were mixed. The resulting mixturecontains 1.2 mole % of a structure unit having a sulfonic acid group inthe total of the polycarboxylic acid-derived structure unit and thepolyhydric alcohol-derived structure unit constituting polyester. Themixture was fed into a twin screw extruder at a flow rate of 10 kg/hrfor kneading at 175° C., and 2.1 mass parts of TDI was fed into theresin mixture during kneading and conveying the resin mixture forfurther kneading to obtain a resin (B3-1). In the resin (B3-1), thestructure and tin indicated in the formula (1) were not contained. Thephysical properties of the obtained resin were shown in Table 8.

Resin (B3-2) to Resin (B3-4)

Resins (B3-2) to (B3-4) were produced in the same manner as in thepreparation of the resin (B3-1), except that the raw materialcompositions were changed to the contents in Table 8. The physicalproperties thereof were shown in Table 8. TABLE 8 Resin B3-1 B3-2 B3-3B3-4 Raw material resin (mass part) b3-1 53 b3-1 53 b3-2 53 b3-4 75 b3-317 b3-3 17 b3-3 17 b3-3 25 b1-4 30 b3-5 30 b3-5 30 TDI (mass part) 2.12.1 2.1 2.1 Content of sulfonic acid group 1.2 1.4 1.4 1.1 (mole %)Polyisocyanate-derived structure Yes Yes Yes Yes Bisphenol A-derivedstructure unit No No No No Content of tin (ppm) 0 0 0 0 Physical Tg (°C.) 61 60.5 60.5 55.5 properties THF insoluble 7 7.4 7.4 10 component(mass %) Peak molecular 6,700 6,100 6,100 6,000 weight

Performance as a toner was evaluated according to the following methodand criteria.

(Fixing Properties)

An unfixed image was formed using a copier produced by remodeling of acommercial electrophotographic copier. The unfixed image was fixed usinga heat roller fixing apparatus produced by remodeling of the fixingsection of a commercial copier. The fixing of a toner was conducted at afixing speed of the heat roll of 210 mm/sec with the temperature of theheat roller being changed at intervals of 5° C. The fixed image obtainedwas rubbed 10 times by applying a load of 0.5 kgf using a sand eraser (aproduct of Tombow Pencil Co., Ltd.), and the image densities before andafter the rubbing test were measured using a Macbeth reflectiondensitometer. The lowest fixing temperature at which the change ratio ofimage density became not less than 60% was taken as the lowest fixingtemperature of the toner. The heat roller fixing apparatus used had nosilicon oil feeder. The environmental conditions were under normaltemperature and normal pressure (temperature=22° C., relativehumidity=55%).

1: Lowest fixing temperature≦170° C.

2: 170° C.<lowest fixing temperature≦190° C.

3: 190° C.<Lowest fixing temperature

(Offset Resistance)

The offset resistance was evaluated according to the above measurementof the lowest fixing temperature. After an unfixed image was formedusing the above copier; the toner image was transferred and fixed usingthe above heat roller fixing apparatus. Then, a white transfer paper wasfed into the heat roller fixing apparatus under the same conditions; andthe appearance of toner staining on the transfer paper was examinedvisually. This operation was repeated by gradually increasing the settemperature of the heat roller of the heat roller fixing apparatus. Thelowest set temperature at which toner staining appeared on the transferpaper was taken as the temperature of offset appearance. The atmosphereof the above copier was a temperature of 22° C. and a relative humidityof 55%.

1: 240°≦Temperature of offset appearance

2: 220° C. ≦temperature of offset appearance<240° C.

3: Temperature of offset appearance<220° C.

(Cleaning properties)

After continuous copying of 5,000 copies was conducted under atemperature of 22° C. and a relative humidity of 55% using the abovecopier contamination of a sensitive material was evaluated visually.

1: Not contaminated at all

2: A little contaminated

3: Fairly contaminated

(Storage stability)

The toner was allowed to stand under the environmental conditions of atemperature of 45° C. and a relative humidity of 60% for 24 hours, and 5g thereof was fed into a sieve of 150 mesh. Then, the scale of arheostat of a powder tester (HOSOKAWA POWDER TECHNOLOGY RESEARCHINSTITUTE) was set to 3 for vibrating it for 1 minute. After vibration,the mass remained on the sieve of 150 mesh was measured to obtain theresidual mass ratio.

1: Less than 25%

2: Not less than 25% and not more than 40%

3: Greater than 40%

Example 1

91 mass parts of the resin (A-2-1), 5 mass parts of a carbon blackREGAL330R (a product of Cabot Specialty Chemicals, Inc.), 3 mass partsof refined carnauba wax 1 powder (a product of Nippon Wax Co., Ltd.) and1 mass part of a charge controlling agent BONTRON S-34 (a product ofOrient Chemical Industries, Ltd.) were dispersed and mixed using aHenschel mixer. The resulting material was fed into a twin screwextruder PCM30-41.5 (a product of Ikegai Corporation) at 3.6 kg/hr andmelt-kneaded at 140° C., and distilled water was continuously fed from afeeding port placed at a vent section of the extruder at 960 g/hr toobtain an aqueous dispersed system comprising a microparticle dispersedin water. An average particle diameter of 50% volume (D50) of theobtained microparticle was 0.29 μm.

The solid content ratio of the aqueous dispersed system was adjusted tobe 20 mass %. 300 g of the aqueous dispersed system and 400 g of 2weight % sodium chloride aqueous solution were fed into a stainlessflask, and stirred and mixed at 30° C. for 30 minutes using CLEARMIX (aproduct of Emtec Co., Ltd.) to aggregate at a prescribed particlediameter. Then, 800 g of distilled water was added thereto. Theresulting material was kept at 90° C. for 6 hours for the thermalfusion, and cooled down to a room temperature, followed by filtering,washing and drying. To 100 mass parts of the solid content obtained inthis manner, 0.1 mass part of a hydrophobic silica (Aerosil R972, aproduct of Nippon Aerosil Co., Ltd.) was added and mixed to obtain atoner. D50 of the obtained toner was 7.5 μm. With regard to the toner,fixing properties and offset resistance were determined using acommercial copier, and the degree of contamination of the heat rollerwas examined. Further, cleaning properties and storage stability testswere carried out. The results thereof are shown in Table 9.

Example 2

A toner was obtained in the same manner as in Example 1, except that theresin (A-2-2) was used as a raw material and the concentration of thesodium chloride aqueous solution was changed to 1.5 mass %. Theevaluation results are shown in Table 9.

Example 3

A toner was obtained in the same manner as in Example 1, except that 64mass parts of the resin (A-2-3) was used as a raw material and 27 massparts of WR-901 (a product of Nippon Synthetic Chemical Industry Co.,Ltd.) was used as a emulsifying auxiliary. The evaluation results areshown in Table 9.

Example 4

A toner was obtained in the same manner as in Example 1, except that 64mass parts of the resin (A-2-3) was used as a raw material, 27 massparts of WR-960 (a product of Nippon Synthetic Chemical Industry Co.,Ltd.) was used as a emulsifying auxiliary, 0.1 normal sodium hydroxideaqueous solution was continuously fed from a feeding port placed at avent section of the extruder at 960 g/hr. The evaluation results areshown in Table 9.

Example 5

A toner was obtained in the same manner as in Example 1, except that 81mass parts of the resin (A-2-3) was used as a raw material and 10 massparts of sodium dodecylbenzene sulfonate was used as a emulsifyingauxiliary. The evaluation results are shown in Table 9.

Example 6

99 mass parts of the resin (A-2-2) and 1 mass part of a chargecontrolling agent BONTRON S-34 (a product of Orient Chemical Industries,Ltd.) were dispersed and mixed using a Henschel mixer. Then, theresulting material was fed into a twin screw extruder PCM30-41.5 (aproduct of Ikegai Corporation) at 3.6 kg/hr and melt-kneaded at 140° C.,and distilled water was continuously fed from a feeding port placed at avent section of the extruder at 960 g/hr to obtain an aqueous dispersedsystem comprising a microparticle dispersed in water. D50 of theobtained microparticle was 0.23 μm. The solid content ratio of theaqueous dispersed system was adjusted to be 20 mass %.

20.0 mass parts of refined carnauba wax 1 powder (a product of NipponWax Co., Ltd.), 2.0 mass parts of Neoperex F-25 (a product of KaoCorporation) and 78.0 mass parts of ion exchange water were heated at140° C. and emulsified at a discharge pressure of 560×10⁵ N/m² using agaulin homogenizer, and then chilled to obtain an aqueous dispersedsystem of a releasing agent. D50 of a releasing agent in the dispersedsystem was 0.12 μm.

20.0 mass parts of a carbon black REGAL33OR (a product of CabotSpecialty Chemicals, Inc.), 5.0 mass parts of Neoperex F-25 (a productof Kao Corporation) and 75.0 mass parts of ion exchange water were mixedand dispersed at an oscillating frequency of 28 kHz for 10 minutes usingan ultrasonic wave cleaning machine W-113 manufactured by HondaElectronics Co., Ltd. to obtain an aqueous dispersed system of acolorant. D50 of a colorant in the dispersed system was 0.15 μm.

270 g of the microparticle aqueous dispersed system, 20 g of thecolorant dispersed system, 10 g of the releasing agent dispersed systemand 400 g of 2 weight % sodium chloride aqueous solution were fed into astainless flask and stirred and mixed at 30° C. for 30 minutes usingCLEARMIX (a product of Emtec Co., Ltd.) to form an aggregate at aprescribed particle diameter. Then, 800 g of distilled water was addedthereto. The resulting material was kept at 90° C. for 6 hours for thethermal fusion, and cooled down to a room temperature, followed byfiltering, washing and drying. To 100 mass parts of the obtained solidcontent, 0.1 mass part of a hydrophobic silica (Aerosil R972, a productof Nippon Aerosil Co., Ltd.) was added and mixed to obtain a toner Anaverage particle diameter of 50% volume of the obtained toner was 6.5μm. The evaluation results of the toner are shown in Table 9. TABLE 9Example/Comparative Example Nos. Comparative Example 1 Example 2 Example3 Example 4 Example 5 Example 6 Example 1 Raw material resin A-2-1 A-2-2A-2-3 A-2-3 A-2-3 A-2-2 A-2-1 Resin D50 (μm) 0.29 0.3 0.29 0.35 0.310.23 — microparticle D90/D10 2.1 2.1 2.1 2.1 2.1 2.1 — Content of lessthan less than less than less than less than less than — organic 10 1010 10 10 10 solvent (ppm) Toner D50 (μm) 7.5 6.2 6.5 7.5 6.2 6.5 11.3D90/D10 1.5 1.5 1.5 1.5 1.5 1.5 2.1 Content of less than less than lessthan less than less than less than 840 organic 10 10 10 10 10 10 solvent(ppm) Fixing 1 1 1 1 1 1 1 properties Offset 1 1 1 1 1 1 2 resistanceCleaning 1 1 1 1 1 1 3 properties Storage 1 1 1 1 1 1 3 stability

Example 7

100 mass parts of the resin (B1-1) was fed into a twin screw extruderPCM30-41.5 (a product of Ikegai Corporation) at 3.6 kg/hr andmelt-kneaded at 140° C., and distilled water was continuously fed from afeeding port placed at a vent section of the extruder at 960 g/hr toobtain an aqueous dispersed system of a resin microparticle for a toner.A particle diameter of 50% volume (D50) of the obtained resinmicroparticle for a toner was 0.32 μm, D90/D10 was 2.1, 5.0 mass partsof the THF insoluble component was included, a polyisocyanate-derivedstructure in the THF insoluble component was confirmed, and the peakmolecular weight of the THF soluble component was 5,500. The ratio ofthe resin microparticle for a toner in the dispersed system was adjustedto be 30 mass %.

20.0 mass parts of refined carnauba wax 1 powder (a product of NipponWax Co., Ltd.), 2.0 mass parts of Neoperex F-25 (a product of KaoCorporation) and 78.0 mass parts of ion exchange water were heated at140° C. and emulsified at a discharge pressure of 560×10⁵ N/m² using agaulin homogenizer, and then chilled to obtain a dispersed system with areleasing agent dispersed therein. An average particle diameter of 50%volume of a releasing agent in the dispersed system was 0.12 μm.

20.0 mass parts of a carbon black REGAL33OR (a product of CabotSpecialty Chemicals, Inc.), 5.0 mass parts of Neoperex F-25 (a productof Kao Corporation) and 75.0 mass parts of ion exchange water were mixedand dispersed at an oscillating frequency of 28 kHz for 10 minutes usingan ultrasonic wave cleaning machine W-113 manufactured by HondaElectronics Co., Ltd. to obtain a dispersed system with a colorantdispersed therein. An average particle diameter of 50% volume of acolorant in the dispersed system was 0.15 μm.

310 mass parts of the dispersed system comprising a resin microparticlefor a toner, 20 g of the colorant dispersed system, 20 mass parts of thereleasing agent dispersed system and 500 g of 0.75 weight % sodiumhydroxide aqueous solution were fed into a stainless flask and stirredand mixed at 30° C. at 5,000 rpm for 30 minutes using CLEARMIX (aproduct of Emtec Co., Ltd.). Then, the resulting material was aggregatedat 65° C. at 8,000 rpm until a prescribed particle diameter wasobtained. Then, 800 mass parts of distilled water was added thereto. Theresulting material was kept at 85° C. for 4 hours for the thermal fusionand cooled down to a room temperature, and then 50 mass parts of 0.5mass % calcium chloride aqueous solution was added thereto, followed byfiltering, washing and drying. To 100 mass parts of the obtained solidcontent, 0.1 mass part of a hydrophobic silica (Aerosil R972, a productof Nippon Aerosil Co., Ltd.) was added and mixed to obtain a toner. Anaverage particle diameter of 50% volume of the obtained toner was 4.7μm.

Fixing properties and offset resistance of this toner were determinedand the degree of contamination of the heat roller was examined.Further, cleaning properties, storage stability and chargeability weredetermined. The evaluation results are shown in Table 10.

Examples 8 to 10

A microparticle dispersed system and a toner were prepared and evaluatedin the same manner as in Example 1, except that the raw materials werechanged to the contents in Table 10. The evaluation results are shown inTable 10. TABLE 10 Example/Comparative Example Nos. Com- Example ExampleComparative Comparative parative Example 7 Example 8 Example 9 10 19Example 2 Example 3 Example 4 Raw material resin B1-1 B1-2 B1-3 B1-4B1-1 — B1-5 B1-1 Resin D50 (μm) 0.32 0.25 0.49 0.24 0.25 — — —microparticle D90/D10 2.1 2.8 3 2.1 2.3 — — — Content of organic lessthan less than less than less than less than — — — solvent 10 10 10 1010 Content of THF 5 7 2.8 2 5.2 — — — insoluble componentPolyisocyanate-derived Yes Yes Yes Yes Yes — — — structure Peakmolecular weight 5,500 7,000 5,400 5,500 7,000 — — — Toner D50 (μm) 4.75 6.3 4.9 6 6.1 6.5 6 D90/D10 1.5 1.5 1.5 1.5 1.5 1.5 2.1 2.8 Content oforganic less than less than less than less than less than 520 840 lessthan solvent 10 10 10 10 10 10 Fixing properties 1 1 1 1 1 2 1 2 Offsetresistance 1 1 1 1 1 3 1 2 Cleaning properties 1 1 1 1 1 1 3 1 Storagestability 1 1 1 1 1 1 3 1 Charging performance 1 1 1 1 1 1 2 1

Example 11

A dispersed system comprising a resin microparticle for a toner andwater was obtained in the same manner as in Example 7, except that theresin (B2-1) was used instead of the resin (B1-1). A particle diameterof 50% volume (D50) of the obtained resin microparticle for a toner was0.30 μm, D90/D10was 1.5, 5.2 mass parts of the THF insoluble componentwas included, a polyisocyanate-derived structure in the THF insolublecomponent was confirmed, a vinyl copolymer in the resin was confirmed,and the peak molecular weight of the THF soluble component was 5,500.Using the dispersed system, a toner was obtained in the same manner asin Example 7. D50 of the obtained toner was 4.7 μm.

Examples 12 to 14

A microparticle dispersed system and a toner were prepared and evaluatedin the same manner as in Example 11, except that the raw materials werechanged to the contents in Table 11. The evaluation results are shown inTable 11. TABLE 11 Example/Comparative Example Nos. Example 11 Example12 Example 13 Example 14 Raw material resin B2-1 B2-2 B2-3 B2-4 ResinD50 (μm) 0.3 0.35 0.31 0.32 microparticle D90/D10 1.5 1.6 1.5 1.5Content of organic less than 10 less than 10 less than 10 less than 10solvent Content of THF 5.2 5.8 6 5.3 insoluble componentPolyisocyanate-derived Yes Yes Yes Yes structure Vinyl Yes Yes Yes Yescopolymer-derived structure Peak molecular weight 5,500 5,500 5,5006,100 Toner D50 (μm) 4.7 5.5 5 4.8 D90/D10 1.5 1.5 1.5 1.5 Content oforganic less than 10 less than 10 less than 10 less than 10 solventFixing properties 1 1 1 1 Offset resistance 1 1 1 1 Cleaning properties1 1 1 1 Storage stability 1 1 1 1 Charging performance 1 1 1 1

Example 15

An aqueous dispersed system obtained by dispersing a resin microparticlefor a toner was obtained in the same manner as in Example 7, except thatthe resin (B3-1) was used instead of the resin (B1-1). In that resinmicroparticle, a bisphenol A-derived structure and tin were notincluded. A particle diameter of 50% volume (D50) of the obtained resinmicroparticle for a toner was 0.31 μm, D90/D10 was 2.0, 5.3 mass partsof the THF insoluble component was included, a polyisocyanate-derivedstructure in the THF insoluble component was confirmed, and the peakmolecular weight of the THF soluble component was 6,700. Using thedispersed system, a toner was obtained in the same manner as in Example7. D50 of the obtained toner was 4.9 μm. The evaluation results areshown in Table 12.

Examples 16 to 18

Microparticle dispersed systems and toners were prepared and evaluatedin the same manner as in Example 15, except that the raw materials werechanged to the contents in Table 12. The evaluation results are shown inTable 12. TABLE 12 Example/Comparative Example Nos. Example 15 Example16 Example 17 Example 18 Raw material resin B3-1 B3-2 B3-3 B3-4 ResinD50 (μm) 0.31 0.29 0.29 0.4 microparticle D90/D10 2 2 2 2.5 Content oforganic less than 10 less than 10 less than 10 less than 10 solvent(ppm) Content of THF 5.3 5.9 5.8 7.9 insoluble componentPolyisocyanate-derived Yes Yes Yes Yes structure Peak molecular weight6,700 6,100 6,000 6,000 Bisphenol A-derived No No No No structureContent of tin (ppm) 0 0 0 0 Toner D50 (μm) 4.9 4.7 4.8 5.1 D90/D10 1.51.5 1.5 1.5 Content of organic less than 10 less than 10 less than 10less than 10 solvent (ppm) Fixing properties 1 1 1 1 Offset resistance 11 1 1 Cleaning properties 1 1 1 1 Storage stability 1 1 1 1 Chargingperformance 1 1 1 1

Example 19

A dispersed system comprising a resin microparticle for a toner andwater was obtained in the same manner as in Example 7 using the resin(B1-1). A particle diameter of 50% volume (D50) of the obtained resinmicroparticle for a toner was 0.32 μm, D90/D10 was 2.1, 7.0 mass partsof the THF insoluble component was included, a polyisocyanate-derivedstructure in the THF insoluble component was confirmed, and the peakmolecular weight of the THF soluble component was 7,000. Using thedispersed system, a toner was obtained in the same manner as in Example7, except that 0.78% sodium chloride aqueous solution was used. Anaverage particle diameter of 50% volume of the obtained toner was 6.0μm. The evaluation results are shown in Table 10.

Comparative Example 1

91 mass parts of the resin (A-2-1), 5 mass parts of a carbon blackREGAL33OR (a product of Cabot Specialty Chemicals, Inc.), 3 mass partsof refined carnauba wax 1 powder (a product of Nippon Wax Co., Ltd.), 1mass part of a charge controlling agent BONTRON S-34 (a product ofOrient Chemical Industries, Ltd.) and 100 mass parts of ethyl acetatewere dispersed for 48 hours using a ball mill. 100 mass parts ofdistilled water was fed into a stainless flask and stirred usingCLEARMIX (a product of Emtec Co., Ltd.). While stirring, 50 mass partsof the above dispersion was slowly fed thereinto, and mixed andsuspended. Then, the solvent was removed under a reduced pressure,followed by washing and drying. To 100 mass parts of the obtained solidcontent, 0.1 mass part of a hydrophobic silica (Aerosil R972, a productof Nippon Aerosil Co., Ltd.) was added and mixed to obtain a toner. Anaverage particle diameter of 50% volume (D50) of the obtained toner was11.3 μm. The evaluation results of the toner are shown in Table 9.

Comparative Example 2

A 5-liter, 4-necked flask was provided with a reflux condenser, anitrogen gas inlet tube, a thermometer and a stirrer. Thereinto were fed47.6 mass parts of ion exchange water, 37.0 mass parts of styrene, 3.0mass parts of n-butyl acrylate, 0.6 mass part of acrylic acid, 2.4 massparts of dodecanethiol, 0.4 mass part of carbon tetrabromide and 4.0mass parts of Neoperex F-25 (a product of Kao Corporation). While theresulting material was dispersed and emulsified in the flask and slowlymixed for 10 minutes, 5.0 mass parts of ion exchange water in which 0.4mass part of ammonium persulfate was dissolved was fed thereinto and theflask was purged with nitrogen. The flask was stirred for carrying outthe emulsion polymerization at 70° C. for 5 hours. Thus, a styrene resindispersion 1 having an average particle diameter of 50% volume of 0.16nm, Tg of 59° C. and the weight-average molecular weight of 12,000 wasobtained.

A 5-liter, 4-necked flask was provided with a reflux condenser, anitrogen gas inlet tube, a thermometer and a stirrer. Thereinto were fed50.2 mass parts of ion exchange water, 28.0 mass parts of styrene, 12.0mass parts of n-butyl acrylate, 0.8 mass part of acrylic acid and 4.0mass parts of Neoperex F-25 (a product of Kao Corporation). While theresulting material was dispersed and emulsified in the flask and slowlymixed for 10 minutes, 5.0 mass parts of ion exchange water in which 0.3mass part of ammonium persulfate was dissolved was fed thereinto and theflask was purged with nitrogen. The flask was stirred for carrying outthe emulsion polymerization at 70° C. for 5 hours. Thus, a styrene resindispersion 2 having an average particle diameter of 50% volume of 105nm, Tg of 53° C. and the weight-average molecular weight of 55,000 wasobtained.

20.0 mass parts of refined carnauba wax 1 powder (a product of NipponWax Co., Ltd.), 2.0 mass parts of Neoperex F-25 (a product of KaoCorporation) and 78.0 mass parts of ion exchange water were heated at140° C. and emulsified at a discharge pressure of 560×10⁵ N/m² using agaulin homogenizer, and then chilled to obtain a releasing agentdispersion. An average particle diameter of 50% volume of the releasingagent dispersion was 0.12 μm. Furthermore, 20.0 mass parts of a carbonblack REGAL33OR (a product of Cabot Specialty Chemicals, Inc.), 5.0 massparts of Neoperex F-25 (a product of Kao Corporation) and 75.0 massparts of ion exchange water were mixed and dispersed at an oscillatingfrequency of 28 kHz for 10 minutes using an ultrasonic wave cleaningmachine W-113 manufactured by Honda Electronics Co., Ltd. to obtain acolorant dispersion. An average particle diameter of 50% volume of thecolorant dispersion was 0.15 μm.

180 g of the styrene resin dispersion 1, 80 g of the styrene resindispersion 2, 30 g of the colorant dispersion, 30 g of the releasingagent dispersion and 1.5 g of sanisol B-50 (a product of KaoCorporation) were mixed and dispersed in a circular flask using a homomixer, and then the flask was stirred in an oil bath and heated up to50° C. The resulting material was kept at 50° C. for an hour.Thereafter, 9.0 g of Neoperex F-25 was added thereto. Then, the flaskwas sealed and heated up to 105° C. while stirring, and kept for 3hours. The mixture was cooled down to a room temperature, followed byfiltering, washing and drying. To 100 mass parts of the obtained solidcontent, 0.1 mass part of a hydrophobic silica (Aerosil R972, a productof Nippon Aerosil Co., Ltd.) was added and mixed to obtain a toner. Anaverage particle diameter of 50% volume of the obtained toner was 6.1μm. Fixing properties and offset resistance of this toner weredetermined and the degree of contamination of the heat roller wasexamined. Further, cleaning properties, storage stability andchargeability were determined. The evaluation results of this toner areshown in Table 10.

Comparative Example 3

A mixture of 15 mass parts of a carbon black REGAL33OR (a product ofCabot Specialty Chemicals, Inc.), 3.5 mass parts ofγ-(2-aminoethyl)aminopropyltrimethoxysilane (a product of Dow ComingToray Silicone Co., Ltd.) and 81.5 mass parts of diethylether wasdispersed for 5 hours using a ball mill. Then, the pressure was reducedat 50° C. for removing the solvent and pretreatment of the carbon blackwas carried out. 4 mass parts of the carbon black, 92 mass parts of theresin (A1-5), 4 mass parts of refined carnauba wax 1 powder (a productof Nippon Wax Co., Ltd.), 150 mass parts of diethylether and 150 massparts of dichloromethane were dispersed for 24 hours using a ball mill.500 mass parts of 2% gum Arabic aqueous solution was fed into astainless flask and stirred using CLEARMIX (a product of Emtec Co.,Ltd.). While stirring, 50 mass parts of the above dispersion was slowlyintroduced. The resulting material was mixed and dispersed at 8,000 rpmfor 8 minutes. The dispersion was fed to distilled water of 2,000 massparts and stirred at 75° C. for 8 hours using a three one motor and thenkept at 95° C. for an hour. 1,000 mass parts of distilled water was putthereinto and cooled down to a room temperature, followed by washing anddrying. To 100 mass parts of the obtained solid content, 0.1 mass partof a hydrophobic silica (Aerosil R972, a product of Nippon Aerosil Co.,Ltd.) was added and mixed to obtain a toner. An average particlediameter of 50% volume of the obtained toner was 6.5 μm. Fixingproperties and offset resistance of this toner were determined and thedegree of contamination of the heat roller was examined. Further,cleaning properties, storage stability and chargeability weredetermined. The evaluation results are shown in Table 10.

Comparative Example 4

100 parts of the resin (B1-1), 4.3 parts of a carbon black REGAL33OR (aproduct of Cabot Specialty Chemicals, Inc.) and 4.3 parts of refinedcarnauba wax 1 powder (a product of Nippon Wax Co., Ltd.) were dispersedand mixed using a Henschel mixer. Then, the resulting material wasmelt-kneaded at 180° C. using a twin screw extruder PCM-30 (a product ofIkegai Corporation) to obtain a toner composition in the bulk state. Thecomposition after melt-kneading was coarsely ground using a hammer mill.The coarsely ground resin was finely ground using a jet grinder (IDS2, aproduct of Nippon Pneumatic Co., Ltd.), followed by air classification,to obtain a toner particle. To 100 mass parts of the obtained tonerparticle, 0.1 mass part of a hydrophobic silica (Aerosil R972, a productof Nippon Aerosil Co., Ltd.) was added and mixed to obtain a toner. Anaverage particle diameter of 50% volume of the obtained toner was 6.0μm. The evaluation results are shown in Table 10.

(Method for Producing Resin)

A polyether polyol based resin was used as a resin.

Resin (C-1)

A separable flask was provided with a stirrer, a thermometer, a nitrogeninlet and a reflux tube. Thereinto were fed 91 mass parts ofpolyoxypropylene-(1,1)-2,2-bis(4-hydroxyphenyl)propane (KB-280, aproduct of Mitsui Takeda Chemicals, Inc.) and 70 mass parts of phthalicanhydride. The resulting material was stirred at an internal temperatureof 100° C. until the system became homogeneous. Subsequently, 0.08 masspart of benzyldimethylamine (BDMA) was added as a catalyst, and thenheated to 130° C. and reacted for 6 hours. After the reaction mixturewas cooled down to not more than 50° C., 110 mass parts of bisphenol A,340 mass parts of low molecular weight bisphenol A type liquid epoxyresin [EPOMIK (registered trademark) R-140P, a product of MitsuiChemicals, Inc., epoxy equivalent: 188 (g/Eq)], 128 mass parts of highmolecular weight bisphenol A type solid epoxy resin [EPOMIK (registeredtrademark) R-309, a product of Mitsui Chemicals, Inc., epoxy equivalent:2,630 (g/Eq)], 52 mass parts of benzoic acid and 9 mass parts of stearicacid were fed thereinto and 0.03 mass part of 50% tetramethylammoniumchloride aqueous solution was added thereto at 80° C. After theresulting mixture was reacted at 160° C. for an hour, 0.03 mass part of50% tetramethylammonium chloride aqueous solution was further addedthereto. The reflux tube was replaced by a vacuum distillation unit andthe degree of decompression was increased little by little for removingthe water. After an hour, the degree of decompression reached 1,333 Pa(10 mmHg). After the mixture was stirred for 2 hours, the pressure inthe reaction system was returned to a normal pressure and stirring wascontinued for 7 hours. At that time, the generated polyol resin wassampled for measuring the epoxy equivalent. The epoxy equivalent wasconfirmed to be not less than 20,000, and then the generated polyolresin was taken out of the flask to obtain a resin (C-1). The softeningpoint of the obtained resin was 124° C., Tg was 59° C., Mn was 3,400, Mwwas 75,000, Mw/Mn was 22, and the hydroxyl value was 158 KOHmg/g.

Resin (C-2)

A separable flask was provided with a stirrer, a thermometer, a nitrogeninlet and a reflux tube. Thereinto were fed 91 mass parts ofpolyoxypropylene-(1,1)-2,2-bis(4-hydroxyphenyl)propane (KB-280, aproduct of Mitsui Takeda Chemicals, Inc.) and 70 mass parts of phthalicanhydride. The resulting material was stirred at an internal temperatureof 100° C. until the system became homogeneous. Subsequently, 0.08 masspart of benzyldimethylamine (BDMA) was added as a catalyst, and thenheated to 130° C. and reacted for 6 hours. After the reaction mixturewas cooled down to not more than 50° C., 233 mass parts of bisphenol A,603 mass parts of low molecular weight bisphenol A type liquid epoxyresin [EPOMIK (registered trademark) R-140P, a product of MitsuiChemicals, Inc., epoxy equivalent: 188 (g/Eq)], 123 mass parts of highmolecular weight bisphenol A type solid epoxy resin [EPOMIK (registeredtrademark) R-309, a product of Mitsui Chemicals, Inc., epoxy equivalent:2,630 (g/Eq)], 90 mass parts of benzoic acid and 22 mass parts ofstearic acid were fed thereinto and 0.03 mass part of 50%tetramethylammonium chloride aqueous solution was added thereto at 80°C. The resulting mixture was reacted at 160° C. for an hour, and then0.03 mass part of 50% tetramethylammonium chloride aqueous solution wasfurther added thereto. The reflux tube was replaced by a vacuumdistillation unit and the degree of decompression was increased littleby little for removing the water. After an hour, the degree ofdecompression reached 1,333 Pa (10 mmHg). After the mixture was stirredfor 2 hours, the pressure in the reaction system was returned to anormal pressure and stirring was continued for 7 hours. At that time,the generated polyol resin was sampled for measuring the epoxyequivalent. The epoxy equivalent was confirmed to be not less than20,000, and then the generated polyol resin was taken out of the flaskto obtain a resin (C-2). The softening point of the obtained resin was113° C., Tg was 60° C., Mn was 2,900, Mw was 21,000, Mw/Mn was 7.2, andthe hydroxyl value was 141 KOHmg/g.

Resin (C-3)

100 mass parts of the resin (C-2) was fed into a twin screw extruder ata flow rate of 10 kg/hr and kneaded at 175° C., and 2.0 mass parts oftolylene diisocyanate (TDI) was fed into the resin mixture duringkneading and conveying the resin mixture for further kneading to obtaina resin (C-3). Tg of the obtained resin was 63° C., Mn was 3,000, Mw was90,000, Mw/Mn was 30, and the hydroxyl value was 136 KOHmg/g.

Emulsifying auxiliary (D-1)

A 5-liter, 4-necked flask was provided with a reflux condenser, awater-separating unit, a nitrogen gas inlet tube, a thermometer and astirrer. Thereinto were fed 66.0 mole of ethylene glycol (EG), 10.0 moleof triethylene glycol (TEG), 24.0 mole of diethylene glycol (DEG), 60.0mole of terephthalic acid (TPA), 20 mole of isophthalic acid (IPA) and20.0 mole of sodium 5-sulfoisophthalic acid. Dehydration andpolycondensation were conducted at 180° C. to 240° C. with nitrogenbeing introduced into the flask to obtain a emulsifying auxiliary (D-1).Tg of (D-1) was 47° C., Mn was 2,300 and Mw was 50,000.

Herein, performance as a toner was evaluated as follows.

(Fixing Properties)

An unfixed image was formed using a copier produced by remodeling of acommercial electrophotographic copier. The unfixed image was fixed usinga heat roller fixing apparatus produced by remodeling of the fixingsection of a commercial copier. The fixing of a toner was conducted at afixing speed of the heat roll of 190 mm/sec with the temperature of theheat roller being changed at intervals of 5° C. The fixed image obtainedwas rubbed 6 times by applying a load of 1.0 kgf using a sand eraser (aproduct of Tombow Pencil Co., Ltd.), and the image densities before andafter the rubbing test were measured using a Macbeth reflectiondensitometer. The lowest fixing temperature at which the change ratio ofimage density became not less than 60%, was taken as the lowest fixingtemperature of the toner. The heat roller fixing apparatus used had nosilicon oil feeder. The environmental conditions were under normaltemperature and normal pressure (temperature=22° C., relativehumidity=55%).

(Evaluation Criteria)

1: Lowest fixing temperature≦160° C.

2: 160° C.<Lowest fixing temperature

(Offset Resistance)

The offset resistance was evaluated according to the above measurementof the lowest fixing temperature. After an unfixed image was formedusing the above copier; the toner image was transferred and fixed usingthe above heat roller fixing apparatus. Then, a white transfer paper wasfed into the heat roller fixing apparatus under the same conditions; andthe appearance of toner staining on the transfer paper was examinedvisually. This operation was repeated by gradually increasing the settemperature of the heat roller of the heat roller fixing apparatus. Thelowest set temperature at which toner staining appeared on the transferpaper was taken as the temperature of offset appearance. The atmosphereof the above copier was a temperature of 22° C. and a relative humidityof 55%.

(Evaluation Criteria)

1:170° C.≦Temperature of offset appearance

2: Temperature of offset appearance<170° C.

(Gloss)

According to the above measurement of the lowest fixing temperature, asolid image fixed at 150° C. was formed and gloss was measured at anincident angle of 75 degrees using a gloss meter GM-3D (a product ofMurakami Color Research Laboratory).

(Evaluation Criteria)

1: 10%≦Gloss

2: Gloss<10%

(Cleaning properties)

After conducting continuous copying of 5,000 copies at 22° C. and arelative humidity of 55% using the above copier, contamination of asensitive material was visually examined.

(Evaluation Criteria)

1: Not contaminated at all

2: Contamination confirmed

(Storage stability)

The toner was allowed to stand for 24 hours under the environmentalconditions of a temperature of 40° C. and a relative humidity of 60%,and 5 g thereof was fed into a sieve of 150 mesh. Then, the scale of arheostat of a powder tester (HOSOKAWA POWDER TECHNOLOGY RESEARCHINSTITUTE) was set to 3 for vibrating it for 1 minute. After vibration,the mass remained on the sieve of 150 mesh was measured to obtain theresidual mass ratio.

(Evaluation Criteria)

1: Residual mass ratio<25%

2: 25%≦Residual mass ratio

Example 20

64.8 mass parts of the resin (C-1), 27.8 mass parts of the emulsifyingauxiliary (D-1), 5 mass parts of a cyanine dye FG7351 (a product of ToyoInk Mfg. Co., Ltd.) and

2.3 mass parts of refined carnauba wax 1 powder (a product of Nippon WaxCo., Ltd.) were dispersed and mixed using a Henschel mixer. Theresulting material was fed into a twin screw extruder PCM30-41.5 (aproduct of Ikegai Corporation) at 3.6 kg/hr and melt-kneaded at 100° C.,and distilled water was continuously fed from a feeding port placed at avent section of the extruder at 1.3 kg//hr to obtain a microparticleaqueous dispersion. An average particle diameter of 50% volume of theobtained microparticle aqueous dispersion was 0.6 μm. The solid contentof the microparticle aqueous dispersion was adjusted to be 30 mass %.200 g of the microparticle aqueous dispersion and 200 g of 0.5 mass %sodium hydroxide aqueous solution were fed into a stainless flask, andstirred and mixed at 30° C. for 30 minutes using CLEARMIX (a product ofEmtec Co., Ltd.). Then, 350 g of distilled water was added thereto. Theresulting material was kept at 70° C. for 6 hours for the aggregationand fusion, and cooled down to a room temperature, followed byfiltering, washing and drying. To 100 mass parts of the solid contentobtained in this manner, 0.1 mass part of a hydrophobic silica (AerosilR972, a product of Nippon Aerosil Co., Ltd.) was added and mixed toobtain a toner. An average particle diameter of 50% volume of theobtained toner was 7.2 μm. For this toner, fixing properties and offsetproperty were determined by using a commercial copier, and gloss wasexamined. Further, cleaning properties and storage stability tests werecarried out. The results thereof are shown in Table 13 along with thoseof other Examples and Comparative Examples.

Examples 21 and 22

Toners were obtained in the same manner as in Example 20, except thatthe raw materials illustrated in Table 13 were used.

Example 23

A toner was obtained in the same manner as in Example 20, except that anichigo polyester WR-901 (a product of The Nippon Synthetic ChemicalIndustry Co., Ltd.), i.e., a polyester containing a sulfonic acid groupwas used instead of the emulsifying auxiliary (D-1). The evaluationresults are shown in Table 13.

Example 24

A toner was obtained in the same manner as in Example 20, except that anichigo polyester W-0223 (a product of The Nippon Synthetic ChemicalIndustry Co., Ltd.), i.e., a polyester containing a sulfonic acid groupwas used instead of the emulsifying auxiliary (D-1). The evaluationresults are shown in Table 13.

Example 25

64.8 mass parts of the resin (C-1) and 27.8 mass parts of a nichigopolyester W-0223 (a product of The Nippon Synthetic Chemical IndustryCo., Ltd.), i.e., a polyester containing a sulfonic acid group were fedinto a twin screw extruder PCM30-41.5 (a product of Ikegai Corporation)at 3.6 kg/hr and melt-kneaded at 120° C., and distilled water wascontinuously fed from a feeding port placed at a vent section of theextruder at 1.3 kg/hr to obtain a microparticle aqueous dispersion. Anaverage particle diameter of 50% volume of the obtained microparticleaqueous dispersion was 0.5 μm. The solid content of the microparticleaqueous dispersion was adjusted to be 20 mass %. Furthermore, 20.0 massparts of refined carnauba wax 1 powder (a product of Nippon Wax Co.,Ltd.), 2.0 mass parts of Neoperex F-25 (a product of Kao Corporation)and 78.0 mass parts of ion exchange water were heated at 140° C. andemulsified at a discharge pressure of 560×10⁵ N/m² using a gaulinhomogenizer, and then chilled to obtain a releasing agent dispersion. Anaverage particle diameter of 50% volume of this releasing agentdispersion was 0.12 μm. Further, 20.0 mass parts of a cyanine dye FG7351(a product of Toyo Ink Mfg. Co., Ltd.), 5.0 mass parts of Neoperex F-25(a product of Kao Corporation) and 75.0 mass parts of ion exchange waterwere mixed and dispersed at an oscillating frequency of 28 kHz for 10minutes using an ultrasonic wave cleaning machine W-113 (a product ofHonda Electronics Co., Ltd.) to obtain a colorant dispersion. An averageparticle diameter of 50% volume of this colorant dispersion was 0.15 μm.270 g of the microparticle aqueous dispersion, 20 g of the colorantdispersion, 10 g of the releasing agent dispersion and 400 g of 2 mass %sodium hydroxide aqueous solution were fed into a stainless flask, andstirred and mixed at 30° C. for 30 minutes using CLEARMIX (a product ofEmtec Co., Ltd.). Then, 800 g of distilled water was added thereto. Theresulting material was kept at 70° C. for 6 hours for the aggregationand fusion, and cooled down to a room temperature, followed byfiltering, washing and drying. To 100 mass parts of the obtained solidcontent, 0.1 mass part of a hydrophobic silica (Aerosil R972, a productof Nippon Aerosil Co., Ltd.) was added and mixed to obtain a toner. Theevaluation results are shown in Table 13.

Example 26

A toner was obtained in the same manner as in Example 20, except that amagenta dye TONER MAGENTA E02 (a product of Clariant Ltd.) was usedinstead of the cyanine dye FG7351 (a product of Toyo Ink Mfg. Co.,Ltd.). The evaluation results are shown in Table 13.

Example 27

A toner was obtained in the same manner as in Example 20, except that ayellow dye TONER YELLOW HG VP2155 (a product of Clariant Ltd.) was usedinstead of the cyanine dye FG7351 (a product of Toyo Ink Mfg. Co.,Ltd.). The evaluation results are shown in Table 13.

Comparative Example 4

A toner was produced and evaluated in the same manner as in ComparativeExample 1. The evaluation results are shown in Table 13.

Comparative Example 5

92 mass parts of the resin (C-1), 5 mass parts of a cyanine dye FG7351(a product of Toyo Ink Mfg. Co., Ltd.), 3 mass parts of refined carnaubawax 1 powder (a product of Nippon Wax Co., Ltd.) and 200 mass parts ofethyl acetate were dispersed for 48 hours using a ball mill. 200 massparts of distilled water and 100 mass parts of 10% tricalcium phosphateslurry were fed into a stainless flask and stirred using CLEARMIX (aproduct of Emtec Co., Ltd.). While stirring, 100 mass parts of the abovedispersion was slowly fed, and mixed and suspended. Thereafter, thesolvent and tricalcium phosphate were removed under a reduced pressureand the resulting material was washed and dried. To 100 mass parts ofthe obtained solid content, 0.1 mass part of a hydrophobic silica(Aerosil R972, a product of Nippon Aerosil Co., Ltd.) was added andmixed to obtain a toner. The evaluation results are shown in Table 13.TABLE 13 Example/Comparative Example Nos. Example Example ExampleExample Example 20 21 22 23 24 Raw material resin C-1 C-2 C-3 C-1 C-1Emulsifying auxiliary D-1 D-1 D-1 WR-901 W-0223 Resin D50 (μm) 0.6 1.10.5 0.9 0.6 microparticle D90/D10 2.8 2.8 2.8 2.8 2.8 Content of lessthan less than less than less than less than organic solvent 10 10 10 1010 (ppm) Toner D50 (μm) 7.2 6.0 6.5 7.1 7.3 D90/D10 1.5 1.5 1.5 1.5 1.5Content of less than less than less than less than less than organicsolvent 10 10 10 10 10 (ppm) Fixing properties 1 1 1 1 1 Offsetresistance 1 1 1 1 1 Cleaning 1 1 1 1 1 properties Storage stability 1 11 1 1 Gloss 1 1 1 1 1

TABLE 14 Example/Comparative Example Nos. Example Example ExampleComparative Comparative 25 26 27 Example 5 Example 6 Raw material resinC-1 C-1 C-1 — C-1 Emulsifying auxiliary W-0223 W-0223 W-0223 — — ResinD50 (μm) 0.5 0.5 0.6 — — microparticle D90/D10 2.8 2.8 2.8 — — Contentof less than less than less than — — organic solvent 10 10 10 (ppm)Toner D50 (μm) 6.5 7.3 7.3 6.1 11.3 D90/D10 1.5 1.5 1.5 1.5 2.1 Contentof less than less than less than 520 840 organic solvent 10 10 10 (ppm)Fixing 1 1 1 2 1 properties Offset 1 1 1 1 1 resistance Cleaning 1 1 1 12 properties Storage stability 1 1 1 1 2 Gloss 1 1 1 2 1

A microparticle aqueous dispersion and a toner obtained by theaggregation and fusion of the microparticle aqueous dispersion accordingto the present invention are confirmed to have excellent fixingproperties, offset resistance, gloss, cleaning properties and storagestability.

1. A resin microparticle (A) for a toner raw material satisfying all ofthe following requirements (i) to (iii): Requirement (i): A particlediameter of 50% volume (D50) satisfies the relationship 0.05 μm≦D50≦1μm; Requirement (ii): A particle diameter of 10% volume (D10) and aparticle diameter of 90% volume (D90) satisfy the relationshipD90/D10≦7; and Requirement (iii): The content of an organic solvent isnot more than 70 ppm.
 2. The resin microparticle (A) for a toner rawmaterial according to claim 1, comprising a polyester based resin (B).3. The resin microparticle (A) for a toner raw material according toclaim 2, wherein the polyester based resin (B) is a polyester basedresin (B1) having a sulfonic acid group.
 4. The resin microparticle (A)for a toner raw material according to claim 3, wherein the polyesterbased resin (B1) is a polyester based resin (B11) having a vinyl basedcopolymer-derived structure (C).
 5. The resin microparticle (A) for atoner raw material according to claim 3, wherein the polyester basedresin (B1) is a polyester based resin (B12) which does not contain abisphenol A-derived structure unit and has the content of tin of notmore than 5 ppm.
 6. The resin microparticle (A) for a toner raw materialaccording to claim 1, comprising a polyether polyol based resin (D). 7.An aqueous dispersed system comprising the resin microparticle (A) for atoner raw material as described in claim 6 dispersed in water.
 8. Atoner comprising the resin microparticle (A) for a toner raw material asdescribed in claim
 6. 9. An aqueous dispersed system comprising theresin microparticle (A) for a toner raw material as described in claim 1dispersed in water.
 10. An aqueous dispersed system comprising the resinmicroparticle (A) for a toner raw material as described in claim 2dispersed in water.
 11. An aqueous dispersed system comprising the resinmicroparticle (A) for a toner raw material as described in claim 3dispersed in water.
 12. An aqueous dispersed system comprising the resinmicroparticle (A) for a toner raw material as described in claim 4dispersed in water.
 13. An aqueous dispersed system comprising the resinmicroparticle (A) for a toner raw material as described in claim 5dispersed in water.
 14. A toner comprising the resin microparticle (A)for a toner raw material as described in claim
 1. 15. A toner comprisingthe resin microparticle (A) for a toner raw material as described inclaim
 2. 16. A toner comprising the resin microparticle (A) for a tonerraw material as described in claim
 3. 17. A toner comprising the resinmicroparticle (A) for a toner raw material as described in claim
 4. 18.A toner comprising the resin microparticle (A) for a toner raw materialas described in claim 5.